customer performance measurement
Transcrição
customer performance measurement
UNIVERSITY OF FRIBOURG SWITZERLAND UNIVERSITÄT FREIBURG SCHWEIZ DEPARTMENT OF INFORMATICS SEMINAR FOR MARKETING AND COMMUNICATION DEPARTEMENT FÜR INFORMATIK SEMINAR FÜR MARKETING & UNTERNEHMENSKOMMUNIKATION Master Thesis Presented to the Faculty of Economics, University of Fribourg, Switzerland In Partial Fulfilment of the Requirements for the Degree of Master of Arts in Management CUSTOMER PERFORMANCE MEASUREMENT Analysis of the Benefit of a Fuzzy Classification Approach in Customer Relationship Management Author: Darius Zumstein Address: Route du Champ-des-Fontaines 24 1700 Fribourg (Switzerland) E-Mail: dzumstein(at)gmx.ch Homepage: www.dzumstein.ch Mobile: +41 (0)78 870 95 55 Place of origin: Burgdorf/Seeberg BE Matriculation #: 00-201-327 1st Reader: 2nd Reader: Prof. Dr. Maurizio Vanetti Prof. Dr. Andreas Meier Tutor: Nicolas Werro Date: Fribourg, 7th of March 2007 Abstract Customers are the most valuable asset of a company. As a result, customers have to be classified, analysed, evaluated, segmented and managed according to their value for the company using appropriate tools and methods of Customer Relationship Management (CRM). This master thesis proposes fuzzy classification as a multidimensional data analysis and management method suitable for realising these CRM processes and for establishing profitable customer relationships. In contrast to other data mining and statistical methods, fuzzy classification and fCQL (fuzzy Classification Query Language) allow the classification of customers into more than one class at the same time. The application of the fuzzy classification approach to widely used management tools like the SWOT, portfolio and ABC analysis and to scoring models enables a better and fairer classification, segmentation and management of customers. So far, these methods have mostly been applied uncritically with sharp classes, although sharp segmentation can obviously be very arbitrary, imprecise, unfair and discriminatory and may have negative effects. The application of the fuzzy portfolio analysis within the scope of performance measurement is especially suited to classifying, analysing, evaluating and improving important monetary customer performance indicators, like turnover, contribution margins, profit and customer equity, and non-monetary indicators, such as customer value, satisfaction, loyalty and retention. Surprisingly, little research has been done on Customer Performance Measurement (CPM) and customer performance indicators despite the increasing theoretical and practical importance of CRM. This work discusses a holistic customer performance measurement framework with 170+ Customer Performance Indicators (CPIs) and relevant Key Customer Performance Indicators (KCPIs). To avoid misclassifications, to improve the quality of customer evaluations and to exploit customer potential, it is suggested to classify all indicators fuzzily. Customer performance indicators for revenue and profitability, and customer investment, relationship, recommendation, information and cooperation indicators allow to segment customers precisely, to optimise fuzzy classified customer portfolios, to drive the proposed CRM success chain and to define customer strategies in order to increase corporate profits and growth. Key words: Fuzzy classification, fuzzy Classification Query Language (fCQL), Customer Relationship Management (CRM), analytical CRM (aCRM), customer performance measurement, customer performance indicators, fuzzy customer segmentation, management tools, fuzzy portfolio analysis, fuzzy credit rating. -I- Kurzfassung Kunden sind die wertvollste Ressource eines Unternehmens. Deshalb müssen Kunden durch geeignete Instrumente des Customer Relationship Managements (CRM) entsprechend ihrem Wert für das Unternehmen analysiert, klassifiziert, beurteilt, segmentiert und behandelt werden. Diese Arbeit schlägt unscharfe Klassifikation als eine Analyse- und Managementmethode vor, um solche CRM-Prozesse umzusetzen und profitable Kundenbeziehungen aufzubauen. Die unscharfe Klassifikation und fCQL (fuzzy Classification Query Language) verbinden fuzzy logic mit relationalen Datenbanken und erlauben im Gegensatz zu anderen Data Mining und statistischen Methoden, dass Kunden mehreren Klassen gleichzeitig angehören können. Wird der Ansatz der unscharfen Klassifikation auf weit verbreitete Managementinstrumente wie etwa auf die Portfolio-, SWOT-, ABC-Analyse oder Scoring-Modelle angewendet, können Kunden besser und fair klassifiziert, segmentiert und gehandhabt werden. Bis anhin wurden diese Methoden der Kundensegmentierung unkritisch mit trennscharfen Klassen durchgeführt, obwohl scharfe Segmentierung offensichtlich sehr willkürlich, ungenau und diskriminierend sein kann, und womöglich negative Auswirkungen nach sich zieht. Unscharfe Klassifikationen und unscharfe Portfolioanalysen können gerade im Rahmen des Performance Measurement nutzbringend eingesetzt werden, um monetäre Kundenkennzahlen (z.B. Umsätze, Deckungsbeiträge, Gewinne, Kundenwert) und nicht-monetäre Kennzahlen (Kundennutzen, -zufriedenheit, -loyalität oder -bindung) zu beurteilen und zu verbessern. Trotz der grossen theoretischen und praktischen Bedeutung des CRMs gibt es erstaunlicherweise wenig Literatur zu Kundenkennzahlen und zu Kundenkennzahlensystemen. Deshalb diskutiert diese Arbeit ein Customer Performance Measurement (CPM) Framework mit 170+ Customer Performance Indicators (CPIs) und zentralen Key Customer Performance Indicators (KCPIs), und empfiehlt diese unscharf zu klassifizieren and zu bewerten. Kennzahlen über die Kundenprofitabilität, -investitionen und die Kundenbeziehung, sowie über das Weiterempfehlungs-, Informations- und Kooperationsverhalten von Kunden, erlauben den Verantwortlichen, unscharf klassifizierte Kundenportfolios zu optimieren, sowie an den wichtigen und richtigen Stellen der vorgeschlagenen CRM-Erfolgskette die Hebel anzusetzen und Kundenstrategien umzusetzen, um damit dem Unternehmen zu höherem Gewinn und Wachstum zu verhelfen. Stichworte: Unscharfe Klassifikation, fuzzy Classification Query Language (fCQL), Customer Relationship Management (CRM), analytisches CRM, Kundenkennzahlensystem, Kundenkennzahlen, unscharfe Kundensegmentierung, Management Tools, unscharfe Portfolioanalyse, unscharfe Kreditwürdigkeitsprüfung. - II - Contents Abstract .................................................................................................................................... I Contents ................................................................................................................................ III List of Figures.........................................................................................................................V List of Tables .....................................................................................................................VIII List of Abbreviations........................................................................................................... IX Acknowledgement ............................................................................................................... XI CHAPTER 1: INTRODUCTION .............................................................................. 1 1.1 1.2 1.3 1.4 Motivation ............................................................................................................... 2 Problem Statement ................................................................................................. 3 Objectives ............................................................................................................... 4 Outline of the Thesis............................................................................................... 5 CHAPTER 2: FUZZY CLASSIFICATION .................................................................7 2.1 The Approach of Fuzzy Classification .................................................................... 8 2.1.1 2.1.2 2.1.3 2.1.4 2.1.5 2.2 Classification as a Database Schema Extension...................................................8 Fuzzy Classification with Linguistic Variables ......................................................10 Aggregation Operator...........................................................................................11 Multidimensional Fuzzy Classification..................................................................13 Dynamic Fuzzy Classification...............................................................................16 Fuzzy Classification Query Language (fCQL) ...................................................... 17 2.2.1 2.2.2 2.2.3 2.2.4 Introduction...........................................................................................................17 Fuzzy Classification Query Examples..................................................................17 Architecture of the fCQL Toolkit ...........................................................................18 Advantages of Fuzzy Classification and fCQL .....................................................20 CHAPTER 3: FUZZY CLASSIFICATION MANAGEMENT TOOLS ........................... 22 3.1 Potential Business Applications for Fuzzy Classification...................................... 23 3.1.1 3.1.2 3.2 Fuzzy Portfolio Analysis........................................................................................ 25 3.2.1 3.2.2 3.2.3 3.3 Definition ..............................................................................................................31 Sharp Classification and Disadvantages..............................................................31 Fuzzy Classification and Advantages ..................................................................32 Fuzzy ABC Analysis ............................................................................................. 35 3.4.1 3.4.2 3.4.3 3.5 Definition ..............................................................................................................25 Sharp Classification and Disadvantages..............................................................26 Fuzzy Classification and Advantages ..................................................................27 Fuzzy SWOT Analysis .......................................................................................... 31 3.3.1 3.3.2 3.3.3 3.4 Overview ..............................................................................................................23 Existing Literature on Marketing and Fuzzy Classification...................................24 Definition ..............................................................................................................35 Sharp Classification and Disadvantages..............................................................35 Fuzzy Classification and Advantages ..................................................................36 Fuzzy Scoring Methods ........................................................................................ 39 3.5.1 3.5.2 3.5.3 Definition ..............................................................................................................39 Sharp Classification and Disadvantages..............................................................39 Fuzzy Classification and Advantages ..................................................................40 - III - Contents CHAPTER 4: ANALYTICAL CUSTOMER RELATIONSHIP MANAGEMENT ............. 44 4.1 Customer Relationship Management (CRM)........................................................ 45 4.1.1 4.1.2 4.1.3 4.1.4 4.1.5 4.2 Customer Performance Measurement.................................................................. 54 4.2.1 4.2.2 4.3 Overview ..............................................................................................................45 The Development to the Customer Oriented Company.......................................46 CRM and Customer Management .......................................................................47 Definition of CRM .................................................................................................49 Objectives and Key Points of CRM ......................................................................51 Definitions.............................................................................................................54 Processes of Customer Performance Measurement ...........................................55 Customer Performance Indicators ........................................................................ 57 4.3.1 4.3.2 4.3.3 Definitions.............................................................................................................57 Categories of Customer Performance Indicators.................................................58 Customer Performance Indicators in Business Practice......................................61 CHAPTER 5: FUZZY CUSTOMER SEGMENTATION ............................................. 62 5.1 Fuzzy Customer Segmentation with Important Indicators .................................... 63 5.1.1 5.1.2 5.1.3 5.1.4 5.1.5 5.1.6 5.1.7 5.1.8 5.1.9 5.1.10 5.1.11 5.1.12 5.1.13 5.1.14 5.1.15 5.1.16 5.2 Definitions.............................................................................................................63 Fuzzy Clustering...................................................................................................64 Methods of Customer Segmentation....................................................................65 Selected Indicators for Fuzzy Customer Segmentation.......................................69 Customer Orientation ...........................................................................................70 Customer Value....................................................................................................71 Customer Satisfaction ..........................................................................................72 Customer Loyalty .................................................................................................73 Customer Retention .............................................................................................75 Repurchases ........................................................................................................78 Add-on Selling ......................................................................................................78 Share of Wallet.....................................................................................................79 Turnover ...............................................................................................................81 Contribution Margins ............................................................................................82 Profitability............................................................................................................84 Customer Equity and Customer Lifetime Value (CLV).........................................86 Fuzzy Market Segmentation ................................................................................. 91 CHAPTER 6: FUZZY CREDIT RATING ................................................................ 94 6.1 Methods of Sharp Credit Rating ........................................................................... 95 6.1.1 6.1.2 6.1.3 6.1.4 6.2 Definitions.............................................................................................................95 Subjective Expertise.............................................................................................95 Statistical Methods ...............................................................................................96 Disadvantages of Sharp Credit Rating.................................................................98 Methods of Fuzzy Credit Rating ........................................................................... 99 6.2.1 6.2.2 6.2.3 Existing Literature on Fuzzy Credit Rating...........................................................99 Fuzzy Credit Rating with fCQL...........................................................................101 Other Applications for Fuzzy Classification in Banking......................................106 CHAPTER 7: CONCLUSION ............................................................................. 107 7.1 7.2 7.3 Summary ............................................................................................................ 108 Critical Remarks ................................................................................................. 115 Outlook ............................................................................................................... 117 References and Further Reading ..................................................................................... 118 Appendix............................................................................................................................. 133 Statement............................................................................................................................. 144 - IV - List of Figures Figure 1: Application of Fuzzy Classification to Popular Management Tools .......................... 2 Figure 2: Theoretical Classification of the Master Thesis ........................................................ 5 Figure 3: Structure of the Master Thesis ................................................................................. 6 Figure 4: Structure of Chapter 2: Fuzzy Classification ............................................................ 8 Figure 5: Classification Space defined by Customer Attractiveness & Competitive Position .. 9 Figure 6: Concept of Linguistic Variables .............................................................................. 10 Figure 7: Fuzzy Classification with Membership Functions ................................................... 11 Figure 8: t-Norms, t-Conorms and Averaging Operator......................................................... 12 Figure 9: Three-Dimensional Sharp (a) and Fuzzy (b) Classification .................................... 14 Figure 10: Example of Hierarchical Multidimensional Fuzzy Classification ............................. 15 Figure 11: Dynamic Fuzzy Classification and Implementation of a Trigger Mechanism.......... 16 Figure 12: Architecture of the fQCL Toolkit ............................................................................. 18 Figure 13: Screenshots of the fCQL Toolkit Query Panel........................................................ 19 Figure 14: Examples of Tasks and Methods of Data Mining ................................................... 21 Figure 15: Fuzzy Classification as a Promising Management Tool for Different Fields........... 23 Figure 16: The Boston Consulting Group Matrix (a) and Norm Strategies (b)......................... 26 Figure 17: Sharp (a) and Fuzzy (b) BCG Portfolio................................................................... 26 Figure 18: Sharp (a) and Fuzzy (b) Investments ..................................................................... 28 Figure 19: Balancing of Fuzzy Classified Portfolios................................................................. 29 Figure 20: Sharp (a) and Fuzzy Classified (b) McKinsey/General Electrics Portfolio .............. 30 Figure 21: Sharp (a) and Fuzzy (b) SWOT Matrix ................................................................... 31 Figure 22: Fuzzy Strength (a), Weakness (b), Opportunity (c) and Threat (d) Matrices.......... 32 Figure 23: Sharp (a) and Fuzzy (b) Risk Matrix ....................................................................... 34 Figure 24: Fuzzy ABC Analysis ............................................................................................... 36 Figure 25: Fuzzy ABC Analysis with Different Customer Performance Indicators................... 37 Figure 26: Combination of the Fuzzy Portfolio and ABC Analysis ........................................... 38 Figure 27: Sharp (a) and Fuzzy (b) RFM Method .................................................................... 41 Figure 28: Fuzzy RFM Incentives ............................................................................................ 42 Figure 29: Structure of Chapter 4 and 5 .................................................................................. 45 Figure 30: The Development to the Customer-Oriented Company ......................................... 46 Figure 31: Applications of Fuzzy Classification in the Domain of Customer Management...... 47 Figure 32: Fuzzy Classification and Individual Marketing ........................................................ 48 Figure 33: The Use of Fuzzy Classification in Typical Tasks of CRM ..................................... 49 -V- List of Figures Figure 34: CRM Application Architecture................................................................................. 50 Figure 35: Mobile Analytical Customer Relationship Management ......................................... 51 Figure 36: CRM Success Chain .............................................................................................. 52 Figure 37: Dimensions of Customer Performance Measurement............................................ 54 Figure 38: Processes of Customer Performance Measurement.............................................. 55 Figure 39: Measurement Dimensions of the CPIP ‘Customer Profit’ ....................................... 58 Figure 40: Measurement Dimensions of the CRI ‘Customer Loyalty’ ...................................... 59 Figure 41: Measurement Dimensions of the CReI ‘Number of Customer Recommendations’ 59 Figure 42: CRM Success Chain with 170+ Customer Performance Indicators ....................... 60 Figure 43: Empirical Results of Customer Performance Measurement in Companies............ 61 Figure 44: Fuzzy Methods of Cluster Analysis ........................................................................ 64 Figure 45: Sharp (a) and Fuzzy (b) Customer Segments ........................................................ 65 Figure 46: Methods of Customer Segmentation ...................................................................... 66 Figure 47: Information Dashboard of Relevant Customer Data............................................... 67 Figure 48: Context of Fuzzy Customer Segmentation............................................................. 68 Figure 49: Indicators of the CRM Success Chain for Fuzzy Customer Segmentation ............ 69 Figure 50: Driving the CRM Success Chain by Optimising Fuzzy Classified Portfolios .......... 69 Figure 51: Fuzzy Cost-Benefit Analysis (a) and Portfolio of Customer Orientation (b)............ 70 Figure 52: Examples of Fuzzy Classified Customer Satisfaction Portfolios............................. 72 Figure 53: Loyalty Ladder ........................................................................................................ 73 Figure 54: Examples of Fuzzy Classified Customer Loyalty Portfolios.................................... 74 Figure 55: Determinants of Customer Retention ..................................................................... 75 Figure 56: Controlling Level and Indicators of Customer Retention ........................................ 76 Figure 57: Fuzzy Classified Portfolios of Customer Retention Indicators ................................ 77 Figure 58: Examples of Fuzzy Classified Repurchase Portfolios ............................................ 78 Figure 59: Examples of Fuzzy Classified Add-on Selling Portfolios ........................................ 79 Figure 60: Crisp (a) and Fuzzy (b) Choice............................................................................... 80 Figure 61: Examples of Fuzzy Classified Share of Wallet Portfolios ....................................... 80 Figure 62: Examples of Fuzzy Classified Turnover Portfolios ................................................. 81 Figure 63: Customer Contribution Margin Accounting ............................................................. 82 Figure 64: Fuzzy Classified Customer Contribution Margins Portfolios................................... 83 Figure 65: Fuzzy Classification of Customer Profitability......................................................... 84 Figure 66: Customer Growth Strategies .................................................................................. 85 Figure 67: Examples of Fuzzy Classified Customer Equity Portfolios ..................................... 86 Figure 68: Fuzzy Classified Customer Satisfaction/Equity Portfolio ........................................ 87 Figure 69: Three-Dimensional Fuzzy Classification of Customer Equity ................................. 89 Figure 70: Fuzzy Classified Customer (a) and Prospect (b) Lifetime Value Portfolios ............ 89 - VI - List of Figures Figure 71: Sharp (a) and Fuzzy Classified (b) Customer Equity Pyramid ............................... 90 Figure 72: Sharp Market Segmentation................................................................................... 91 Figure 73: Basic Market-Preferences Patterns ........................................................................ 92 Figure 74: Fuzzy Market Segmentation of Income and Age.................................................... 92 Figure 75: Fuzzy Market Segments and Strategies................................................................. 93 Figure 76: Discriminant Function and Type I and II Errors ...................................................... 96 Figure 77: Architecture of a Neural Network for Credit Rating................................................. 97 Figure 78: Discriminant Functions in Discriminant Analysis and ANN..................................... 97 Figure 79: Hierarchy of Creditworthiness with Weights δ and Parameters γ........................... 99 Figure 80: Credit Rating Hierarchy with the Degree of Importance gi of each Criterion ........ 100 Figure 81: fCQL as a Method of Artificial Intelligence............................................................ 101 Figure 82: Practice-Related Example of a Hierarchy of Creditworthiness ............................. 102 Figure 83: Examples of a Qualitative and a Quantitative Attribute of Fuzzy Credit Scoring .. 102 Figure 84: Hierarchical Fuzzy Classification of Creditworthiness .......................................... 103 Figure 85: Thee-Dimensional Sharp (a) and Fuzzy (b) Credit Rating.................................... 105 Figure 86: Promising Management Tools, Methods and Concepts for Fuzzy Classification . 109 Figure 87: Fuzzy Classified Customer Portfolio (a) and Fuzzy ABC Analysis (b) .................. 110 Figure 88: Tools and Indicators for Customer Performance Measurement ........................... 113 Figure 89: The Main Challenges of Marketing Controlling in Practice ................................... 116 - VII - List of Tables Table 1: Research Questions and Objectives ........................................................................ 4 Table 2: Selected Indicators for Customer Attractiveness and Competitive Position ............. 9 Table 3: Absolute and Normalised Membership Degress of Customer Smith...................... 12 Table 4: Membership Degress of the Customers ................................................................. 14 Table 5: Basic Scheme of SQL and fCQL ............................................................................ 17 Table 6: Criteria for Assessing Industry Attractiveness and Competitive Strength............... 30 Table 7: Sharp ABC Analysis ............................................................................................... 35 Table 8: Fuzzy ABC Analysis ............................................................................................... 36 Table 9: Example of the RFM Method with Sharp Classes .................................................. 39 Table 10: RFM Method: Definition of Classes and Scores ..................................................... 40 Table 11: Sharp RFM Scoring of Customers.......................................................................... 41 Table 12: Fuzzy RFM Scoring of Customers.......................................................................... 42 Table 13: Mass vs. One-to-One Marketing and Applications for Fuzzy Classification ........... 48 Table 14: Drivers of Customer Value and Satisfaction ........................................................... 71 Table 15: Determinants and Indicators of Customer Equity ................................................... 88 Table 16: Interest Rates for Different Loan Categories ........................................................ 105 Table 17: Sharp Classification of the Loan Applicants ......................................................... 105 Table 18: Results of Research Question (RQ) 1 .................................................................. 109 Table 19: Results of Research Question 2........................................................................... 111 Table 20: Results of Research Question 3........................................................................... 111 Table 21: Results of Research Question 4........................................................................... 112 Table 22: Results of Research Question 5........................................................................... 112 Table 23: Results of Research Question 6........................................................................... 114 Table 24: Results of Research Question 7........................................................................... 114 - VIII - List of Abbreviations # aCRM AI ANN BCG BE BP BPR BSC C CAS CCI CCO CII CInfI CIM CLV CP CPI CPM CPMS CPIP CR CRA CRC CReI CRI CRM CRO Cu. DB DBMS DWH(S) e EDGE EDI Ed(s). EGPRS ERP fc FCM fCMT Number analytical Customer Relationship Management Artificial Intelligence Artificial Neural Networks Boston Consulting Group Balance Error Balanced Portfolio Business Process Re-Engineering Balanced Scorecard Class Computer Aided Selling Customer Cooperation Indicator Chief Customer Officer Customer Investment Indicator Customer Information Indicator Computer Integrated Manufacturing Customer Lifetime Value Customer Performance Customer Performance Indicator Customer Performance Measurement Customer Performance Measurement System Customer Performance Indicator for Revenue and Profitability Customer Relation Customer Relationship Analytics Customer Relationship Communication Customer Recommendation Indicator Customer Relationship Indicator Customer Relationship Management Customer Relationship Operations Customer Database Database Management System Data Warehouse (System) electronic Enhanced Data rates for → GSM Evolution Electronic Data Interface Editor(s) Enhanced GPRS (→ GPRS plus → EDGE) Enterprise Ressource Planning fuzzy classification fuzzy-C-Means (algorithm) fuzzy Classification Management Tools - IX - List of Abbreviations fCQL FMLE GPRS GSM HSDPA I ICT IM IS IT KAM KDD KCPI KPI KSF L MD MIS MOA No. OLAP p(p). PDA PM PMS R&D RDBMS RFM ROC(I) ROI ROM(I) ROQ ROR ROS RQ SCM SFA SME SWOT sc SBF SBU SQL TQM UMTS Vol. WLAN fuzzy Classification Query Language Fuzzy-Maximum-Likelihood-Estimation (algorithm) General Packet Radio Service Global System for Mobile Communication High Speed Downlink Packed Access Indicator Information and Communication Technology Information Management Information System Information Technology Key Account Management Knowledge Discovery in Databases Key Customer Performance Indicators Key Performance Indicators Key Success Factor Level Membership Degrees Management Information System Market Opportunity Analysis Number On-Line Analytical Processing page(s) Personal Digital Assistant Performance Measurement Performance Measurement System Research & Development Relational Database Management System Recency, Frequency, Monetary value Return on Customer (Investment) Return on Investment Return on Marketing (Investment) Return on Quality Return on Relationship Return on Sales Research Question Supply Chain Management Sales Force Automation Small and Medium Enterprises Strengths, Weaknesses, Opportunities, Threats sharp classification Strategic Business Field Strategic Business Units Structured Query Language Total Quality Management Universal Mobile Telecommunications System Volume Wireless Local Area Network -X- Acknowledgement Firstly, I thank Nicolas Werro for asking me to write about fuzzy classification and for the excellent assistance. He gave me the opportunity for a very interesting and exciting trip into new worlds. In addition, I want to thank Prof. Dr. Andreas Meier and Prof. Dr. Maurizio Vanetti that this interdisciplinary project could be realised. I am particularly grateful to my parents, Gabriela, Beatus and Jürg, for supporting me in all the years. They made possible, what was and is so important to me. I am also thankful for all the interesting discussions and the good advice of Florian Schramm and Martin Zöller, and for the corrections of Tau Kevin Musa. This thesis is dedicated to Ela, who supported and loved me so much in the last three years – the best ones of my life. - XI - Chapter 1 Introduction -1- Chapter 1: Introduction 1.1 Motivation Since Zadeh first published the article “Fuzzy Sets” in the Journal “Information and Control” in 1965, much scientific research has been done in the field of fuzzy control over all the years. In basic research, many publications have been written on fuzzy logic, fuzzy sets or on fuzzy classification, on different mathematical definitions of the fuzzy classification approach, on its implementations in information systems and on diverse applications in the field of engineering. In fact, fuzzy logic and fuzzy classification is well known in many rather technical disciplines like electronics or engineering, but also in mathematics, statistics, informatics and data mining. In contrast, in marketing and business management fuzzy classification is still largely unknown and rarely used, in both theory and practice. This gap motivated to write this master thesis about the potential and benefit of fuzzy classification in business activities. Consequently, following initial questions raised, which will be discussed in this work in detail and summarised in Chapter 7: there exists an approach of fuzzy classification and the fuzzy Classification Query Language (fCQL). However, ‘where’ can fuzzy classification be used in business management? ‘How’ could fuzzy classification be used? ‘What for’ can fuzzy classification be used? ‘Why’ should fuzzy classification be used? First of all, one management field, which seems to be promising for fuzzy classification, is Customer Relationship Management (CRM). Most researchers and managers have recognised that customers are the most valuable and Average overall satisfaction with a tool scarcest assets of a company. As a result, CRM has become very important in the last years. 4.2 4.1 4.0 3.9 3.8 3.7 Core competencies Strategic alliances Strategic planning Growth strategies (customer acquisition) Customer Supply chain management segmentation Scenario and contingency planning Benchmarking TQM Offshoring CRM Economical value-added analysis Outsourcing Six sigma Mission and vision statement Price optimization models Balanced scorecard Business process reengineering Activity-based Change management management Open market innovation Knowledge management Mass customisation Loyality management 3.6 Promising management tools and fields for fuzzy classification 0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100% Usage of tool (in how many of the asked companies a management tool was used) Scale of satisfaction: 1/2: extremely/somewhat dissatisfied; 3: neither dis-/ nor satisfied; 4/5: somewhat/extremely satisfied; Source data: [Bain & Company 2005, p.13] Figure 1: Application of Fuzzy Classification to Popular Management Tools -2- Chapter 1: Introduction An international study of [Bain & Company 2005], shown in Figure 1, confirms that CRM was applied in 75% of all asked companies and is the second most important management tool in business practice, behind strategic planning (79%) and before customer segmentation (72%) and performance measurement (with the balanced scorecard: 57%). Obviously, most companies were somewhat or very satisfied with the tools. In addition, the management tools seem to be promising for the fuzzy classification approach, as reasoned in the problem statement. 1.2 Problem Statement This thesis will discuss several research questions and problems in the following domains, ‘where’ fuzzy classification can be used: Fuzzy classification has not often been applied to CRM, although it seems to be suited to improve CRM. As a result, a first research question has to be answered: ‘where’, in which CRM fields and processes, ‘how’ and ‘why’ could fuzzy classification improve CRM? To analyse and control marketing or CRM, management needs adequate methods, instrument or tools to evaluate customers. However, what are widely used management tools and methods in business practice suited for fuzzy classification? The thesis will explain, ‘how’ and ‘why’ fuzzy classification can be applied to such management tools. To manage customers according to their importance for the firm, CRM and marketing need a measurement system to analyse and evaluate the performance of customers. Defining another research question and creating a new term: what is the benefit of fuzzy classification in customer performance measurement? Although many authors of literature on CRM, marketing, accounting and information management emphasise the importance of measuring customer relationships and customer performance, there exist surprisingly few reviews and little literature about the measurement of customer performance. To measure customer performance, CRM requires indicators. However, what kind of indicators does CRM need? What are important customer performance indicators for customer performance measurement? The thesis will work out a concept, ‘how’ customer performance indicators could be applied, and ‘why’ and ‘what for’ they are relevant. Customer segmentation, an important task of analytical CRM and data mining, seems to be particularly interesting for fuzzy classification (‘what for’), because it is evidently dangerous to label and classify customers sharply just as "good" (profitable) or "bad" (unprofitable). However, this work argues, ‘how’ and ‘why’ fuzzy classification can be used for an exact, fair and enhanced customer segmentation. With a specific problem of customer segmentation, each loan officer of a bank is confronted: when is a loan applicant creditworthy, and when is he not? Answering this last research question, it will be shown, ‘how’ and ‘why’ fuzzy classification can be used for credit rating. -3- Chapter 1: Introduction 1.3 Objectives This thesis tries to answer seven Research Questions (RQ) and their objectives, mentioned in the problem statement and summarised in Table 1. Answering the research questions and discussing all the points on the right hand side of Table 1, new theoretical insights should be gained about the benefit of the application of the fuzzy classification approach in customer relationship management. The main aim of this master thesis is to show the possibilities for an improved evaluation and management of customers using fuzzy classification. Table 1: Research Questions and Objectives # Research Questions (RQ): Objectives: analysis, discussion and evaluation of the … 1 What are potential fields applications of fuzzy classification: and topics for business overview of different promising marketing fields and concepts for applications of fuzzy classification applications for fuzzy classification in marketing? overview of different potential fuzzy management tools and methods … possible spectrum of marketing concepts and management tools for the 2 3 4 5 6 7 discussion of existing literature on marketing and fuzzy classification … application of the fuzzy classification approach to different management What are potential tools and instruments of analysis and control: management tools definition and advantages of fuzzy portfolio analysis definition and advantages of fuzzy SWOT analysis and methods for fuzzy definition and advantages of fuzzy ABC analysis classification? definition and advantages of fuzzy scoring methods and RFM method … application of fuzzy classification to fields, tasks, processes and instruWhat are potential fields, ments of marketing and Customer Relationship Management (CRM): processes and instruments discussion of promising marketing concepts for fuzzy classification, promising fields for fuzzy classification in customer management/CRM for fuzzy classification in definition, processes, architecture, objectives and key points of CRM CRM? definition of a small CRM success chain … application of the fuzzy classification approach to customer performance What are the benefits measurement and management: of fuzzy classification in definition of the term customer performance definition of the term customer performance measurement customer performance characteristics and processes of customer performance measurement measurement? customer performance measurement in business practice … customer performance indicators and key customer performance What are important indicators for holistic customer performance measurement: customer performance definition of the term customer performance indicator collection, discussion and categorisation of a comprehensive number of indicators for customer performance measurement? customer performance indicators mapping of customer performance indicators to a big CRM success chain … fuzzy segmentation of customers into fuzzy customer segments using important customer performance indicators: How can customers be definition of the term fuzzy customer segmentation methods and context of fuzzy customer evaluation and segmentation segmented fuzzily? fuzzy customer segmentation with 12 Key Customer Performance Indicators (KCPIs) of the CRM success chain using fuzzy portfolio analysis … fuzzy credit rating approach for the evaluation of the creditworthiness of private loan applicants: What are the benefits of discussion and disadvantages of methods of sharp credit rating the fuzzy classification discussion and advantages of methods of fuzzy credit rating approach in credit rating? example of a hierarchical fuzzy classification for credit scoring calculation of personalised interest rates using fuzzy classification The following outline shows, how the thesis is structured and organised in order to work out a clear concept by discussing the seven research questions. -4- Chapter 1: Introduction 1.4 Outline of the Thesis The research questions indicate that the objects of research of this work are intersections of different fields in information management: the fuzzy classification approach with the fuzzy Classification Query Language (fCQL) is actually a topic of computer science and information technology. However, this thesis discusses different business applications for fuzzy classification and is therefore an approach of business management. The main issues of the thesis, customer performance measurement and customer segmentation (research questions 4 to 6), belong both to marketing and managerial accounting. In addition, research question 7, the task of credit rating, can be assigned to finance (compare Figure 2). Marketing Fuzzy classification Objects of research Customer Relationship Management (CRM) Customer performance measurement Customer segmentation Credit rating Accounting Finance Information management Figure 2: Theoretical Classification of the Master Thesis The master thesis has the following structure: The introducing Chapter 2 will summarise the essential ideas, logic, concepts and the model of fuzzy classification and the fuzzy classification Query Language (fCQL). Chapter 3 discusses different potential fields for fuzzy classification (RQ 1) and different fuzzy classification management tools (RQ 2): fuzzy portfolio analysis, fuzzy SWOT analysis, fuzzy ABC analysis and fuzzy scoring methods. Chapter 4 deals with the applications of fuzzy classification within analytical CRM (RQ 3), with the conception of customer performance measurement (RQ 4), and with customer performance indicators (RQ 5). In Chapter 5, the developed concept of customer performance measurement and different important indicators are applied to fuzzy customer segmentation (RQ 6). Methods of sharp and fuzzy credit rating (RQ 7) are discussed in Chapter 6. In Chapter 7, conclusion, all findings are summarised. Critical remarks and an outlook on further research questions about business applications for fuzzy classification will round off the thesis. -5- Chapter 1: Introduction Figure 3 shows the structure of the thesis, including the seven Research Questions (RQ). 1. Introduction 1.1 Motivation 1.2 Problem Statement 1.3 Objectives 1.4 Outline 2. Fuzzy Classification 2.1 The Approach of Fuzzy Classification 2.2 Fuzzy Classification Query Language (fCQL) 3. Fuzzy Classification Management Tools 3.3 Fuzzy SWOT Analysis RQ 2 3.4 Fuzzy ABC Analysis 3.5 Fuzzy Scoring Methods RQ 1 Fuzzy classification and advantages 3.2 Fuzzy Portfolio Analysis Sharp classification and disadvantages 3.1 Potential Business Applications for Fuzzy Classification 4. Analytical Customer Relationship Management 4.1 Customer Relationship Management (CRM) RQ 3 4.2 Customer Performance Measurement RQ 4 4.3 Customer Performance Indicators RQ 5 5. Fuzzy Customer Segmentation 5.1 Fuzzy Customer Segmentation with Important Indicators RQ 6 5.2 Fuzzy Market Segmentation 6. Fuzzy Credit Rating 6.1 Methods of Sharp Credit Rating 6.2 Methods of Fuzzy Credit Rating 7. Conclusion Figure 3: Structure of the Master Thesis -6- RQ 7 Chapter 2 Fuzzy Classification -7- Chapter 2: Fuzzy Classification 2.1 The Approach of Fuzzy Classification 2.1.1 Classification as a Database Schema Extension This technical chapter recapitulates the main findings and research on fuzzy classification of the Information System Research Group at the Department of Informatics at the University of Fribourg (Switzerland). This chapter is based on the research of [Schindler 1998a, Meier et al. 2001, 2003, 2005, Werro 2005, Werro et al. 2005a/b, 2006]. However, the concepts are explained using a new example of fuzzy classification, a customer attractiveness/competitive position portfolio. Figure 4 shows the structure of the chapter. Aggregation Operator Multidimensional Fuzzy Classification Dynamic Fuzzy Classification Fuzzy Classification Query Examples Architecture of the fCQL Toolkit Advantages of Fuzzy Classification and fCQL Linguistic variables, verbal terms, membership degree, continuous and discrete member functions; Aggregation Operator, compensatory, t-norms, t-conorms Multidimensional fuzzy classification, hierarchical fuzzy classification, decomposition principle; Fuzzy classification over time, monitoring, trigger mechanism; fCQL, relational database, fuzzy queries; SQL, fCQL/SQL basic scheme, fCQL syntax; fCQL toolkit, fCQL tool’s architecture, fCQL interpreter; Improved classification, reduction of complexity, extraction of hidden data, no migration, easy to use, etc. [Zimmermann 1992], [Zimmermann and Zysno 1980] Schindler 1998a] [Meier et al. 2005a/b] [Werro et al. 2005] [ Werro et al. 2006] Fuzzy Classification with Linguistic Variables Sharp classification and fuzzy classification; [Chen 1998] [Shenoi 1995] [Meier 2003a] Sharp vs. Fuzzy classification References Attribute, domain, context, database scheme, equivalence class; Classification as a Database Schema Extension Fuzzy Classification Query Language (fCQL) Section 2.2 fCQL Keywords New example: customer attractiveness/competitive position portfolio Section 2.1: Approach of Fuzzy Classification Subsections Figure 4: Structure of Chapter 2: Fuzzy Classification To define classes in the relational database schema, a context model proposed by [Chen 1998] was extended [Meier et al. 2001]: To every attribute Aj, defined by a domain D(Aj), a context K(Aj) is added. A context K(Aj) is a partition of D(Aj) into equivalence classes. A relational database schema with contexts R(A, K) is then the set A = (A1,…, An) of attributes with associated contexts K = (K1(Aj),…,Kn(An)) [Shenoi 1995]. -8- Chapter 2: Fuzzy Classification In this chapter, the following example of CRM with two attributes is considered: customers who buy the company’s products can be evaluated by ‘customer attractiveness’ (attribute A1), which is measured by an index, and ‘competitive position’ (A2). ‘Customer attractiveness’ and ‘competitive position’ can be specified by one or several indicators (combined and weighted by a scoring model or decomposed by a hierarchical classification) shown in Table 2. For explanations, details and more customer indicators see Appendix 4 (pages 136ff). Table 2: Selected Indicators for Customer Attractiveness and Competitive Position Customer attractiveness (A1) Competitive position (A2) Customer turnover or sales (I 31-I 34) Customer contribution margins I – IV (I 70-I 74) Customer gross/net profit (I 75,I 76), profitability (I 78) Customer equity (I 79), Customer Lifetime Value (I 80) Growth of turnover (I 35) or profit (I 77); potential (I 83) Probability of repurchases (I 57), price sensitivity (I 60) Customer’s product mix at the company/competitor (I 58) Punctuality of payment (I 63), creditworthiness (I 68) Number of recommendations (I 152), cooperation (I 171) Customer penetration (I 38) Share of wallet (I 39-I 41) Market share of customer (I 42) Cross- and up-selling (I 50- I 54) Duration of customer relationship (I 147) Satisfaction (I 126), commitment (I 131) Customer loyalty (I 134), retention (I 137) Image of company (I 115), products (I 116) Competitive advantages The pertinent contexts K(Aj) of the two qualifying attributes can be defined as follows: Customer attractiveness (A1): The attribute domain D(A1) of the index ‘customer attractiveness’ is defined by [0, 100] and is divided into the two equivalence classes [0, 49] for ‘unpromising’ customer attractiveness and [50, 100] for ‘promising’ attractiveness. Competitive position (A2): The domain D(A2) is {very bad, bad, insufficient, sufficient, good, excellent} and has two equivalence classes: {very bad, bad, insufficient} for a ‘weak’ competitive position, and {sufficient, good, excellent} for a ‘strong’ one. The definition of the equivalence classes of the two attributes ‘customer attractiveness’ and ‘competitive position’ determines a two-dimensional classification space shown in Figure 5. The four resulting classes C1 to C4 could be characterised as ‘star customers’ (C1) with the strategy to maintain, as ‘development customers’ (C2) in which has to be invested, ‘absorption customers’ (C3) are to skim, and in ‘renunciation customers’ (C4) a firm should not invest. Customer attractiveness 100 C2) 50 49 C1) Development customers (to invest) Star customers (to maintain) C4) C3) Renunciation customers Absorption customers (to skim) (not to invest) 0 very bad bad insufficient sufficient good excellent Competitive position Figure 5: Classification Space defined by Customer Attractiveness and Competitive Position -9- Chapter 2: Fuzzy Classification This portfolio, originally described by [Link and Hildebrand 1993] and discussed by [Homburg and Krohmer 2006], is adapted from the market growth/market share portfolio of the Boston Consulting Group (with the classes C1: ‘stars’, C2: ‘question marks’, C3: ‘cash cows’ and C4: ‘poor dogs’) and from the industry attractiveness/competitive strength portfolio of McKinsey and General Electrics (see Section 3.2 Fuzzy Portfolio Analysis). 2.1.2 Fuzzy Classification with Linguistic Variables In this section, the model will be extended by defining a fuzzy classification database scheme in order to determine the customer’s membership degrees to the different classes. To derive fuzzy classes from sharp contexts, the attributes are considered as linguistic variables, and verbal terms are assigned to each equivalence class [Zimmermann 1992]. With the help of linguistic variables, that means words or word combinations, the equivalence classes of the attributes can be described more intuitively. In the example, the linguistic variable ‘customer attractiveness’ is described by the terms ‘unpromising’ and ‘promising’. The linguistic variable, ‘competitive position’, is divided into the terms ‘weak’ and ‘strong’ (see Figure 6). Customer attractiveness unpromising 0 promising 49 50 [0,..., 49] Competitive position 100 [50,..., 100] Equivalence class Equivalence class weak very bad Linguistic variable (attribute) strong bad insufficient sufficient good Term excellent [very bad, bad, insufficient] [sufficient, good, excellent] Domain Context Equivalence class Equivalence class Figure 6: Concept of Linguistic Variables Every term of the linguistic variable represents a fuzzy set. Each fuzzy set is determined by a membership function (μ) over the whole domain of the corresponding attribute. The attribute ‘customer attractiveness’ contains numerical values in the interval [0,100]. Consequently, the membership functions μunpromising and μpromising are continuous functions. In contrast, the attribute ‘competitive position’ does not hold numerical values, but general terms. In this case, the terms of the linguistic variable ‘weak’ and ‘strong’ are associated to discrete functions, i. e. each term corresponds to a discrete value. Using the context model, linguistic variables and membership functions, the classification space becomes fuzzy. This fuzzy partition has an important outcome, it implies the disappearance of the classes’ sharp borders, that means there are continuous transitions between the different classes [Werro et al. 2006]. - 10 - Chapter 2: Fuzzy Classification μ unpromising 22.9% C2: Development customer 0 1 0.65 0.35 0 Sharply classified customer turnover of the last year Fuzzily classified customer turnover of the last year very bad 0 0.2 0.4 0.6 0.8 1 . Smith Brown C3) 26.4% C3: Absorption customer Smith Brown C4) Renunciation customers (not to invest) . Ford C3) Absorption customers (to skim ) weak strong . . 33.7% C4: Renunciation customer Ford . 25.1% C3: Absorption customer C2) Development customers (to invest) D(Competitive position) 49 50 C4) 31.5% C1: Star customer C1) . Star Miller customers (to maintain) promising Miller 24.5% C2: Development customer 18.9%: C4 Renunciation customer . D(Customer attractiveness) . C1) C2) 17% C1: Star customer Sharp classification 100% C1: Star customer unpromising 100 μ promising D(Customer attractiveness) 100% C4: Renunciation customer bad insufficient sufficient good μ weak excellent D(Competitive position) μ strong Figure 7: Fuzzy Classification with Membership Functions In terms of colour: at the transitions of the classes, the four colours of the classes (in Figure 7), light and dark green, and light and dark blue, become blurred, melt or flow together. Classified fuzzily, a customer can belong to more than one class at the same time and his membership degrees to the different classes can be calculated using an aggregation operator, for instance the γ-operator discussed in the following subsection. The sizes of the circles in Figure 7 are assumed to provide additional information about the customer’s amount of turnover of the last year, since it is common in portfolio analysis to symbolise the importance of a business unit (here: of a customer) by the diameter of the circle. However, the size of circle has nothing to do with the fuzzy classification of the customer itself. 2.1.3 Aggregation Operator The membership degree M(Oi│Ck) of an object Oi (of a customer in the example) in class Ck can be calculated by an aggregation over all terms of the linguistic variables that define the class. Class C1 in the discussed example is described by the terms ‘promising’ and ‘strong’. The membership grade of class C1 (star customers) is therefore a conjunction of the corresponding values of the membership functions μpromising and μstrong. Analogically, C2 is defined by the membership functions μpromising and μweak, C3 (absorption customers) by μunpromising and μstrong and C4 (renunciation customers) by μunpromising and μweak. - 11 - Chapter 2: Fuzzy Classification The used operator of the aggregation is the γ-operator, the “compensatory and”, which was suggested and empirically tested by [Zimmermann and Zysno 1980, Zimmermann 1992]: (1− γ) ⎛ m ⎞ μAi (x) = ⎜ ∏μi (x)⎟ ⎝ i =1 ⎠ γ m ⎛ ⎞ ⎜1− ∏(1- μi (x))⎟ , x ∈ X, 0 ≤ γ ≤ 1 ⎝ i =1 ⎠ (γ-operator) The γ-operator is composed by the algebraic product operator, a t-norm and its counterpart, a t-conorm (compare Figure 8). The t-norms and t-conorms are non-compensatory operations, what means that there is no compensatory effect between the considered elements. In contrast, the averaging operators have a compensation mechanism to reflect the reasoning of humans, who intuitively weigh up elements (for details see [Werro 2007, p. 15]). μ A Gamma = 0.5 μ 1 1 t-conorms B Gamma = 0.6 Gamma = 0 Gamma = 0.8 Gamma = 0.2 Gamma = 1 Gamma = 0.4 0.9 0.8 0.7 0.6 Averaging operators Mu Averaging operators 0.5 0.4 0.3 0.2 t-norms M o 0.1 x 0 Source: adapted from [Werro 2007, p. 15] 1 5 9 13 17 21 25 29 33 37 41 45 49 53 57 61 65 69 73 77 81 85 89 93 97 101 x x Figure 8: t-Norms, t-Conorms and Averaging Operator In all examples of fuzzy classification in this thesis it is assumed that gamma is 0.5 (γ = 0.5; (1− 0.5) red curve in Figure 8), That means that the γ-operator is ⎛ m ⎞ μAi (x) = ⎜ ∏μi (x)⎟ ⎝ i =1 ⎠ m ⎛ ⎞ ⎜1 − ∏ (1- μi (x))⎟ i =1 ⎝ ⎠ 0.5 . The membership degrees of all classified objects Oi (customers) to each class Ck can be calculated be the γ-operator using the fCQL toolkit or the Microsoft® Excel file “GammaOperator” in Appendix 1 (see p. 133). For customer Smith in Figure 7, for instance, the membership degrees are calculated in Table 3. To receive the relative membership degrees Mnorm(Oi│Ck), the absolute degrees M(Oi│Ck) have to be normalised, because the membership degree of an object to a class depends on all other classes and therefore indirectly on the number of classes k (see [Krishnapuram and Keller 1993, Schindler 1998a, p. 165]). Table 3: Absolute and Normalised Membership Degress of Customer Smith Corresponding membership Class functions of each class (C) Customer attractiveness Competitive position Membership degrees of attributes Customer Competitive attractiveness position C1 μpromising μstrong 0.35 0.40 C2 μpromising μweak 0.35 0.60 C3 μunpromising μstrong 0.65 0.40 C4 μunpromising μweak 0.65 0.60 Total - 12 - Absolute membership degrees M(OSmith│Ck): (1−0.5) ⎛m ⎞ μAi (x) = ⎜ ∏μi (x)⎟ ⎝ i =1 ⎠ 0.5 m ⎛ ⎞ ⎜1− ∏(1- μi (x))⎟ ⎝ i =1 ⎠ (.35·.40).5 ·(1 - ((1-.35)·(1-.40))).5 = 0.37417 · 0.78102 = 0.29223 (.35·.60).5·(1 - ((1-.35)·(1-.60))).5 = 0.45826 · 0.86023 = 0.39421 (.65·.40).5·(1 - ((1-.65)·(1-.40))).5 = 0.50990 · 0.88882 = 0.45321 (.65·.60).5·(1 - ((1-.65)·(1-.60))).5 = 0.62450 · 0.92736 = 0.57914 1.71879 Normalised membership degrees Mnorm(OSmith│Ck): M(O i C k ) ∑ (M(O C )) k i k n =1 0.29223 / 1.71879 = 0.17002 0.39421 / 1.71879 = 0.22935 0.45321 / 1.71879 = 0.26368 0.57914 / 1.71879 = 0.33695 1 Chapter 2: Fuzzy Classification Classified sharply (compare Figure 7), customer Smith belongs to one class only, 100% to C4, and he is managed as a renunciation customer not to invest in, like customer Ford, who has much lower values. This is arbitrary, not precise and not fair since Smith has nearly the same values as Brown, who is classified in class C1 as a star customer to maintain. However, Brown’s attractiveness and competitive position is not as high as the ‘real star customer’ Miller ones and still should be improved. These two types of misclassifications are typical for sharp classifications: elements with very similar values can be classified in total different classes, and elements, which have very different values, may be classified in the same class. There often exist high discrepancies between the classes and within a class. With fuzzy classification, this does not happen and the misclassification problem is solved. Classified fuzzily, Smith is no longer discriminated and belongs partly to all classes at same time, as calculated in Table 3 and shown in Figure 7 (17% to C1, 22.9% to C2, 26.4% to C3 and 33.7% to C4). Brown also belongs simultaneously to four classes (31.5% to C1, 24.5% to C2, 25.1% to C3, 18.9% to C4). With fuzzy classification both customer Smith and Brown are not separated anymore and can be managed according to their real degree of ‘customer attractiveness’ and ‘competitive position’. However, Miller (C1) and Ford (C4) still belong to one class only. A class of the fuzzy classification can also be considered as a fuzzy customer segment. For instance, all customers with absolute membership degrees between 0 and 1 to C1 ‘stars’ (in Figure 7) can be considered as a fuzzy segment. Consequently, the fuzzy segment C1 consists of the Miller (with a absolute membership degree 100% to C1), Brown (54.4% to C1) and Smith (29.2% to C1). From the management point of view, this raises important questions: how much should be invested in Brown or Smith, who are positioned in the middle of the matrix and belong partially to different segments (i.e. classes) at the same time? One answer could be that managers have to define customer strategies more specifically, differentiated, and, most important, more individually and personally. 2.1.4 Multidimensional Fuzzy Classification Fuzzy classification as a multidimensional analysis and classification method is not limited to two dimensions. Several attributes or criteria can be considered at the same time. In Figure 9a, a third dimension, the future-oriented attribute ‘customer potential’, with the two terms ‘low potential’ and ‘high potential’, is added to the discussed example. Classified sharply (Figure 9a), Brown and Miller belong to same class (C5), although their positions are very different. Brown and Smith, however, are almost in the same position, but belong to different classes, Brown to C5 and Smith to C3. Classified fuzzily (Figure 9b), the eight classes’ sharp borders disappear and the three dimensional classification space becomes fuzzy. - 13 - Chapter 2: Fuzzy Classification b) Three-Dimensional Fuzzy Classification a) Three-Dimensional Sharp Classification C5) 100% C1) C2) C3) C4) C5) C6) C7) C8) Customer attractiveness Smith unpromising high potential low potential weak Miller Competitive position strong Brown C5) 100% C5) 100% Smith Ford C3) 100% C4) 100% C1) C2) C3) C4) C5) C6) C7) C8) Customer Potential 0.56 0.44 0.57 0.43 μ unpromising promising μ promising Customer attractiveness 12.8% 9.6% 11.2% 8.3% 17.5% 13.4% 15.4% 11.7% Brown 14.9% 13.1% 17.3% 15.2% 9.7% 8.4% 11.5% 9.9% Miller Smith Customer Potential μ high potential 0.64 0.36 0.68 0.32 C3) 42.9% C4) 57.1% Ford 1 0 0 1 0.36 μ low potential Competitive position 0.44 0.38 0.64 0.56 0.62 μ weak μ strong Figure 9: Three-Dimensional Sharp (a) and Fuzzy (b) Classification Brown and Smith belong now to eight different classes, with following absolute M(Oi│Ck) and normalised Mnorm(Oi│Ck) membership degrees in Table 4. Calculation example for Smith to C1: M(OSmith│C1) = (0.43·0.56·0.68)0.5 · ((1 - ((1-0.43)·(1-0.56)·(1-0.68)))0.5 = 0.40465·0.95903 = 0.38808 Mnorm(OSmith│C1) = 0.38808 / 2.60418 = 0.14902 = 14.9% (for details see Appendix 1). Table 4: Membership Degress of the Customers Class C1 C2 C3 C4 C5 C6 C7 C8 Corresponding membership functions to each class μpromising μpromising μunpromising μunpromising μpromising μpromising μunpromising μunpromising μstrong μweak μstrong μweak μstrong μweak μstrong μweak μlow potential μlow potential μlow potential μlow potential μhigh potential μhigh potential μhigh potential μhigh potential Total M(Oi│Ck) Ford 0 0 0.6 0.8 0 0 0 0 1.4 Smith Brown 0.38808 0.33987 0.45157 0.39674 0.25281 0.21772 0.29833 0.25906 2.60418 0.33409 0.25146 0.29126 0.21637 0.45698 0.35045 0.40151 0.30599 2.60811 Mnorm(Oi│Ck) Miller 0 0 0 0 1 0 0 0 1 Ford Smith Brown 0 0 0.42857 0.57143 0 0 0 0 1 0.14902 0.13051 0.17340 0.15235 0.09708 0.08360 0.11456 0.09948 1 0.12810 0.09641 0.11167 0.08296 0.17521 0.13437 0.15395 0.11732 1 Miller 0 0 0 0 1 0 0 0 1 The example of the three-dimensional fuzzy classification in Figure 9b will now be extended to a hierarchical fuzzy classification. The decomposition principle facilitates the definition and the optimisation of the classification while maintaining a small number of classes with a proper semantic even if many attributes are taken into account (see [Werro et al. 2006]). The three attributes ‘customer attractiveness’, ‘competitive position’ and ‘customer potential’, which define the ‘customer equity’ on the top level of the hierarchy, can be decomposed as shown in Figure 10a. The attribute ‘customer attractiveness’, for instance, is defined by three other attributes (in Figure 10c): ‘RFM score’, ‘profit’, and ‘payment history’. The attribute ‘RFM score’ (described in detail in Section 3.5 and shown in Figure 10d) again, consists of the attributes ‘Recency’, ‘Frequency’ and ‘Monetary value’ of the customer’s repurchases. - 14 - Chapter 2: Fuzzy Classification a) Hierarchical Fuzzy Classification of Customers b) Fuzzy Classification of Customer Equity Customer equity Payment history Loyalty Duration or CR Intention to switch C1-1-6) C1-1-2) C1-1-8) C1-1-7) C1-1-3) 1 μ low value 0 1 1 Frequency 0 μ rare μ strong μ weak C1-6) C1-2) C1-8) C1-4) 0 C1-5) C1-1) C1-7) μ C1-3) good μ bad Profit 0 1 μ frequent d) Fuzzy Classification of RFM Score Competitive position RFM score μ high value μ high potential C3) 0 0 1 C1-1-5) μ long ago C1-1-4) 1 Information Cooperation Recommendations C1-1-1) C7) μ low potential Relationship Retention Punct. of payment Method of payment Outstanding bills Recency Down-selling pot. Cross-selling pot. Up-selling pot. Products Services Relationship C4) μ high score Turnover product Turnover service Transaction costs μ recent Add-on selling Satisfaction with C8) μ low score Profit Growth of Profits Turnover Cash flow Customer potential Cu. penetration Share of wallet Cu. market share C1) Payment history Penetration Recency Frequency Monetary value C5) C6) C2) μ unattractive RFM score μ attractive Customer potential Competitive position Monetary value Customer attractiveness Customer attractiveness μ low profit μ high profit c) Fuzzy Classification of Customer Attractiveness Figure 10: Example of Hierarchical Multidimensional Fuzzy Classification In comparison to sharp classifications, for fuzzy classifications fewer terms (equivalence classes) have to be defined in order to describe each attribute. The fuzzy classification of the attribute ‘profit’, for instance, needs two terms only: ‘low profit’ and ‘high profit’. If turnover is classified sharply, much more terms (equivalence classes) have to be defined: e.g. ‘very low’, ‘low’, ‘medium’, ‘high’ and ‘very high’ turnover. However, the lowest hierarchical level of the fuzzy classification in Figure 10a still consists of 27 (3·9) attributes and 54 terms. To reduce complexity and receive a clear semantic, all groups of three attributes at the bottom-level (e.g. ‘Recency’, ‘Frequency’ and ‘Monetary value’) have to be aggregated (to the term ‘RFM score’). The ‘RFM score’, in turn, ‘profits’ and ‘payment history’ express a higher semantic (‘customer attractiveness’) on the next level. Depending on the information demand, customer performance can be analysed on different levels of the hierarchy from a bottom-up or from a top-down approach. The combination of this decomposition principle with a scoring model (see Section 3.5) is a promising approach to develop a comprehensive customer evaluation model based on any customer criteria, which are important for a company. - 15 - Chapter 2: Fuzzy Classification 2.1.5 Dynamic Fuzzy Classification Dynamically, fuzzy classification enables a precise monitoring of the positions and evolutions of a customer, a customer segment or of all customers in a portfolio (see [Werro et al. 2006]). By comparing different values over time, it can be controlled, if customer performance (in Figure 11a) is increasing, steady or decreasing. This facilitates, on the one hand, a comparison of the target and actual business results of a single customer or segment, and, on the other hand, to react quickly and to launch adequate counter measures, if the performance of a customer, of a segment or of the whole portfolio is decreasing rapidly. The identification of important leading-indicators of customer performance, such as the number of orders (I 17), order quote (I 19), repurchase intentions (I 55), cross-buying intentions (I 54), intention to recommend (I 151), customer (dis)satisfaction (I 126), or the intention to switch (I 141), enables the implementation of a trigger mechanism (red-flag-function) which warns at an early stage, if a good customer (Smith in Figure 11) shows a churning behaviour. b) Miller 2007(1) 2006(2) 2006(1) 2006(1) μ unpromising 2006(2) C4 2007(1) Ford X 2007(1) 2006(2) 2006(1) C3 Trigger mechanism for churn management 2006(1) 2006(2) 2007(1) 0 Turnover in term (t) 0 1 Smith’s leading-indicators: Intention to switch satisfaction Smith’s membership degrees to the classes C1, C2, C3, C4 1 Intention to repurchase/cross-buy Number of orders very low 1 Competitive position Brown Smith Implementing a Trigger Mechanism C1 maximum level C2 very high μ promising Customer attractiveness minimum levels a) μ weak 0 2006(1) μ strong 2006(2) 2007(1) t Figure 11: Dynamic Fuzzy Classification and Implementation of a Trigger Mechanism In the fictive example of Figure 11b, Smith suddenly was very dissatisfied with a product or the company itself, therefore his intention to switch highly increased and his intention to repurchase or cross-buy from the company decreased. Brown’s number of orders, and later his turnover, also decreased, when he found an option or substitute elsewhere. As a result, his membership degrees to the "good classes" (C1, C2, C3) steadily decreased from the first term in 2006 to the first term in 2007, and the membership degree to C4 increased accordingly. However, by modelling different leading- and lagging-indicators of customer performance, a trigger mechanism warns, if the membership degrees to different classes fall below a minimum (or exceed a maximum) level. To stop or weaken the negative trend, adequate CRM actions can be launched in order to increase customer satisfaction, loyalty or retention again. - 16 - Chapter 2: Fuzzy Classification 2.2 Fuzzy Classification Query Language (fCQL) 2.2.1 Introduction The fuzzy Classification Query Language (fCQL) is a data analysis or a data mining tool, which combines relational databases with fuzzy logic. This enables the use of numerical and non-numerical values and allows the formulation of linguistic variables, which results in a more human-oriented querying process. fCQL enables the formulation of unsharp queries on a linguistic level, so the user does not need to deal with a fuzzy SQL or with fuzzy predicates, which could lead to varying semantics and different interpretations of the original data collection [Finnerty and Shenoi 1993]. As a result, the user can easily formulate classification queries as they are intuitive, i.e. the meaning of the queries is linguistically expressed. 2.2.2 Fuzzy Classification Query Examples fCQL is an extension of the Structured Query Language (SQL), the international standard for defining and query relational databases. Table 5 shows the comparison of the two languages. Table 5: Basic Scheme of SQL and fCQL SQL Select from where Attribute Relation Condition of Selection fCQL classify from with Object Relation ClassificationCondition Source: [Schindler 1998a] As shown in Table 5, the select clause from the SQL schema is changed to classify, the name of the object column to be fuzzily classified. The where clause turns to with, the predicate for a classification. In the with clause, the user enters the predefined linguistic variables and their associated verbal terms. In combination with keywords, the user generates the classification conditions. After the definition of the fCQL syntax, following fuzzy classification query examples of the discussed customer attractiveness/competitive position portfolio can be undertaken. To query all customers of the customer portfolio, the fCQL query will be: classify from customer customer portfolio In order to ask for new classes, a specific term of a linguistic variable can be queried. For instance, the customer manager wants to know all unpromising customers of the customer attractiveness/competitive position portfolio discussed in Subsection 2.1.2. He queries: - 17 - Chapter 2: Fuzzy Classification classify from with customer customer portfolio customer attractiveness is unpromising Now all membership degrees of the customer based on the function μunpromising are calculated. If the user wants to know the promising and strong customers to invest, he queries: classify from with customer customer portfolio customer attractiveness is promising and competitive position is strong Now he receives the membership degrees of all customers with a membership degree based on the functions μpromising and μstrong. The query returns the predefined class C1 with the semantic ‘star customers’. A simpler way to specify class C1 named ‘star customers’ is as follows: classify from with customer customer portfolio class is star customers Particularly in complex databases, the utility of querying on linguistic variables becomes important. The ability of querying on linguistic variables can be considered as the slicing and dicing operations on a fuzzy multidimensional classification space [Werro et al. 2005a]. 2.2.3 Architecture of the fCQL Toolkit In this subsection, the architecture and the implementation of the fuzzy Classification Query Language (fCQL) will be resumed. By extending the relational database scheme, meta-tables (n in Figure 12) are added to the Relational Database Management System (RDBMS; o). p User or application u Data architect Case 2 Case 1 Case 3 v Graphical interaction fCQL s queries v Membership Function Editor Definition and chart of discrete [a), b)] or continuous, i.e. linear [c), d)] or sshaped [e), f)] membership functions. a) b) 1 fCQL q toolkit SQL r queries 0 c) Generated t SQL queries d) 1 0 Server e) Raw data n Meta-tables f) 1 o Relational Database Management System (RDBMS) 0 Source: adapted from [Werro et al. 2006, p.3] Figure 12: Architecture of the fQCL Toolkit - 18 - Chapter 2: Fuzzy Classification These meta-tables contain the definition of the linguistic variables and terms, the description of the classes and all the meta-information regarding the membership functions. The architecture of the fCQL toolkit illustrates the interactions between the user (p), the fCQL toolkit (q) and the RDBMS. The fCQL toolkit is an additional layer above the relational database system [Werro et al. 2005b]. This particularity makes fCQL independent from underlying database systems based on SQL. Consequently, fCQL can operate with every RDBMS without migrating data and the user can always query the database also with standard SQL queries (r; case 1 in Figure 12). In case 2, the user, or an application, can formulate fuzzy queries (s) to the fCQL toolkit. The query panel of the fCQL toolkit allows analysing the data distribution (1D), data space (2D) and the fuzzy classification (see screenshot in Figure 13). Figure 13: Screenshots of the fCQL Toolkit Query Panel The queries with fCQL are analysed and translated into corresponding SQL statements for the RDBMS (t in Figure 12). In order to generate the fuzzy classification results, the toolkit accesses the raw data as well as the meta-data and computes the membership degrees of the classified elements in the different classes. The classification results are then displayed to the user or returned to the application. Before querying the fCQL toolkit, the data architect (u) has to define the fuzzy classification (case 3). This primarily includes the definition and chart of linear or s-shaped functions with the membership function editor (v). In order to be easily accessible and platform independent, the fCQL toolkit has been implemented as a standalone Java application. Therefore, the user can install the toolkit on all main platforms or operating systems available on the market (e.g. Windows, Mac, Linux, etc.). - 19 - Chapter 2: Fuzzy Classification 2.2.4 Advantages of Fuzzy Classification and fCQL Ce que l'ordinateur a de peu plaisant, c'est qu'il ne sait dire que oui ou non, jamais un peut-être. (Brigitte Bardot, actrice française) Das Unsympathische an Computern ist, dass sie nur ja oder nein sagen können, aber nicht vielleicht. (Brigitte Bardot, französische Filmschauspielerin) Saying this, Brigitte Bardot was definitively not aware of the idea of fuzzy classification discussed in this chapter: computers can say "perhaps" very well, they do not return a "yes" or a "no" only. In fact, the main advantage of fuzzy classification and fCQL is that the membership degree of a classified element to a class can be calculated in a range between 0 and 1. In addition, a classified element is, in contrast to sharp classification, not limited to a single class, but can be assigned to several classes at the same time. With fuzzy classification, the transition between the different classes become fluent, that means continuous. Further advantages of fuzzy classification and fCQL can be summarised so far: fCQL enables the reduction of complexity without loss of information a fair and non-discriminatory classification of customers according to their performance the extraction of hidden data and a better description of the classified elements to consider the potential as well as the possible weaknesses of each classified element the use of numerical values, i.e. quantitative or monetary variables, and non-numerical values, i.e. qualitative or non-monetary variables queries on a linguistic level (that means the formulation of a word or word combinations), an intuitive and human-oriented querying process and a clear semantic the adoption of linguistic variables to the marketing terminology of every company and therefore a facilitated cooperation between marketers and IT specialists that the raw data of relational databases do not have to be migrated or modified the multidimensional classification, evaluation and segmentation of objects, with any number and any kind of attributes or criteria to decompose complex classifications into a hierarchy of classifications a dynamic classification, for instance the monitoring of classified elements over time and the implementation of a trigger mechanism, which warns in case of a negative development of the classified elements. - 20 - Chapter 2: Fuzzy Classification As it will be discussed in Chapter 4, fuzzy classification facilitates the personalisation, individualisation and differentiation of marketing and therefore an improved one-to-one marketing and mass customisation. In addition, fuzzy classification and the fuzzy Classification Query Language (fCQL) as a data mining tool can be used for customer and market segmentation, e.g. for the identification of market segments (compare Figure 14), for classification (e.g. the identification of customer with high turnover) or for performance measurement, e.g. for the detection of Key Customer Performance Indicators (KCPIs). Another objective of data mining and fuzzy classification is the description and visualisation of data. Figure 14 shows these examples of possible tasks for fuzzy classification, other statistical data analysis methods and data mining techniques, which are not considered in this master thesis. For details on data mining and data mining techniques see for instance: [Ester and Sander, 2000, Berry and Linoff 2000, Berson et al. 2000, Drozdenko and Drake 2002, Witten and Frank 2005, Neckel and Knobloch 2005, Han and Kamber 2006, Larose 2006, Williams 2006]. Examples of problems Tasks of data mining Methods of data mining Identification of profitable customer or market segments Segmentation Identification of customers with high turnover Classification Detection of Key Customer Performance Indicators (KCPI) Customer performance measurement Dependency analysis Forecast of turnover X of customer Y for next year Prediction & estimation Artificial neural network Identification and analysis of purchase patterns Market basket analysis Association analysis Presentation of results to the management Description & visualisation Decision trees Cluster analysis Fuzzy classification & fCQL Figure 14: Examples of Tasks and Methods of Data Mining - 21 - Chapter 3 Fuzzy Classification Management Tools - 22 - Chapter 3: Fuzzy Classification Management Tools 3.1 Potential Business Applications for Fuzzy Classification 3.1.1 Overview The fuzzy classification approach and the fCQL toolkit are not just another concept or software of information management. This data mining tool is a powerful instrument for management, for the analysis and control of business processes and results. If adequate data of marketing and accounting is available in an Information System (IS) or in a Management Information System (MIS), fuzzy classification as a data analysis method can be successfully used for Performance Measurement (PM). In the field of Customer Relationship Management (CRM), fuzzy classification can therefore be used for Customer Performance Measurement (CPM). Figure 15 gives a review of fuzzy Classification Management Tools External (market) Internal (company) (fCMT) and the applications to different fields of marketing management. Customer relationship management ¨Section 4.1 Customer performance measurement Fuzzy portfolio analysis ¨Section 4.2 ¨Section 3.2 Fuzzy customer segmentation Fuzzy SWOT analysis ¨Section 5.1 ¨Section 3.3 Fuzzy credit rating Fuzzy ABC analysis ¨Section 6.2 ¨Section 3.4 Fuzzy market segmentation ¨Section 5.2 0.4 0.5 0.3 0.6 0.2 0.1 0 0.468 0.4 0.5 0.3 0.6 0.7 0.2 0.8 0.1 0.9 0 1 0.8 0.1 0.9 0 1 μ high 1 Management = 0.7 0.8 0.964 0.9 1 0 0 0 1 0.739 0.2 μ high 1 Satisfaction Repurchases Cross buying Costs Equity, CLV Return on’s Market analysis Demand Products Structure Development Prices Competition performance indicators for 0.4 0.5 0.3 0.6 0.7 Value Loyalty Retention Turnover Profits Profitability Analysis Analysing and controlling of Control Indicator n Indicator 2 Indicator 1 Performance measurement Fuzzy scoring methods ¨Section 3.5 Marketing and market research Customer Analysis Implementation μ high Production Marketing (e.g. products or customers) Accounting or finance (e.g. sales, profits, etc.) Planning Figure 15: Fuzzy Classification as a Promising Management Tool for Different Fields Figure 15 shows that fuzzy classification can be applied, for example, to management tools; e.g. as fuzzy portfolio analysis, as fuzzy SWOT analysis, as fuzzy ABC analysis and as fuzzy scoring model (content of the Sections 3.2 to 3.5), and to performance measurement to analyse and control any kind of performance indicators of production, marketing, managerial accounting or finance. Section 4.2 focuses on the performance measurement of customers. - 23 - Chapter 3: Fuzzy Classification Management Tools Fuzzy classification supports performance measurement, for instance, in the field of Customer Relationship Management (CRM; discussed in Section 4.1); particularly the task of customer analysis and customer segmentation (content of Section 5.1) production and operations; to fuzzily categorise, analyse and control materials, products, services and production processes and the utilisation of machines or employees. supplier relationship management; to classify and evaluate different suppliers or products segment marketing; to undertake fuzzy market segmentations, to fuzzily target market and to fuzzily position products or companies in markets (content of Section 5.2) credit rating; to fuzzily calculate the degrees of risk, creditworthiness or other data of bank customers (content of Section 6.2). 3.1.2 Existing Literature on Marketing and Fuzzy Classification Surprisingly, only a limited number of reviews, publications or books on fuzzy classification or fuzzy system applications are available in literature on marketing and business management. These cover, for instance: production and operations [Sárfi et al. 1996, Vasant et al. 2004], web mining [Arotaritei and Mitra 2004] and portfolio selection [Inuiguchi and Ramik 2000]. Fuzzy systems have also been applied to credit rating [Levy et al. 1991, Romaniuk and Hall 1992, Weber 1996, Chen and Chiou 1999, Baetge and Heitmann 2000, Hoffmann et al. 2002, Shin and Sohn 2004] and the modelling of fuzzy data in qualitative marketing research [Varki et al. 2000]. In marketing, [Casabayo et al. 2004] used a fuzzy system to identify customers who are most likely to defect to a different grocery retailer when a new retailer establishes itself in the same area. As they state, the value added by fuzzy classification to customer relationship management is the ability to transform customer data into real useful knowledge for taking strategic marketing decisions (see [Vogues and Pope 2006]). [Hruschka 1986] proposed a segmentation of customers using fuzzy clustering methods. A clusterwise regression model for simultaneous fuzzy market structuring was discussed by [Wedel and Steenkamp 1991]. [Fisher et al. 1995] analysed fuzzily socio-economic attributes of older consumers. Hsu’s Fuzzy Grouping Positioning Model [Hsu 2000] enables an understanding of the relationship between consumer consumption patterns and a company’s competitive situation and strategic positioning. However, most of the reviews are basic research and usually do not deal with relational databases. If they do (see [Takahashi 1995, Biewer 1997, Bosc and Pivert 2000, Kacprzyk and Zadrozny 2000, Galindo et al. 2005]), they follow another approach than fCQL does. In the authors’ point of view, practical applications of the fuzzy classification approach both in literature and in business practice of marketing are still insufficient. In view of that, the following chapters will point out further potential of fuzzy classification in the field of marketing, CRM and particularly in customer performance measurement. - 24 - Chapter 3: Fuzzy Classification Management Tools 3.2 Fuzzy Portfolio Analysis 3.2.1 Definition The method of portfolio analysis is often used in the field of strategic management in order to analyse and plan business strategies. According to [Kotler et al. 2005, p. 60], a business portfolio is the collection of businesses, products or customers that make up the company. The portfolio analysis is a tool by which management identifies and evaluates these various businesses. The best business portfolio is the one that fits the company’s strengths to the opportunities in the environment (compare Section 3.3: Fuzzy SWOT Analysis). The company first has to analyse its current business portfolio and decide which businesses should receive more, less or no investment, and second to develop growth strategies for adding new businesses, or, in the case of a customer portfolio, to recruit and bind customers. The most popular portfolio analysis is the market growth/market share matrix, which was developed by the Boston Consulting Group (BCG). It has two axes: ‘real market growth’ and ‘relative market share’, which is determined in comparison with the position of the strongest competitor. The axes define a matrix with four classes, which are usually labelled as ‘stars’, ‘question marks’, ‘cash cows’ and ‘poor dogs’. In the classes, Strategic Business Units (SBU) or Strategic Business Fields (SBF), products, customers or other objects are positioned. A Strategic Business Unit (SBU) is a unit of the company that has a separate mission and objectives, and which can be planned independently from other businesses of the company. [Grünig and Kühn 2005b, p. 133] define a SBU as a business which contributes critically to the success, with its own independent market offer, but whose strategy must be adjusted to those of other business units within the corporation because they operate in the same market and/or share the same resources. The same authors define a Strategic Business Field (SBF) as a business which contributes critically to the success and whose strategy can be planned independently because it has an independent market offer and it does not to any significant extent share markets and/or resources with any other business in the corporation. According to [Kotler et al. 2005, p. 61], the four classes C1 to C4 in Figure 16a can be described as follows: C1) Stars are high-growth, high-share businesses that require heavy investments to finance their rapid growth. Eventually their growth will slow down and they turn into cash cows. C2) Question marks are low-share business units in high-growth markets. They require cash to hold the market share or become stars. Management has to think about the question marks, which ones they should build into stars and which ones they should phase out. C3) Cash cows are low-growth, high-share businesses, products or customers. These established and successful units needs less investment to hold their market share. Thus they produce cash the company uses to invest in other SBUs. - 25 - Chapter 3: Fuzzy Classification Management Tools C1) Stars C4) C3) Cash cows Low Poor dogs Low High Real market growth C2) Question marks Improve dramatically reltive market share and then follow strategy for stars . Or: ▪ Follow strategy for dogs C1) Stars Preserve or increase relative market share Invest in resources or marketing Tolerate negative cash flow C4) Poor dogs Minimize investment Continue while there is positive free cash flow Sell/liquidate businesses, if cash flows are negative C3) Cash cows Preserve relative market share Invest defensively in resources and marketing Maximise cash flows Relative market share C2) Question marks Relative market share b) Life-cycle High a) Real market growth Source (b): adapted from [Grünig and Kühn 2005b, p. 172] Figure 16: The Boston Consulting Group Matrix (a) and Norm Strategies (b) C4) Poor dogs are low-growth, low-share businesses, products or customers. They generate enough cash to maintain them, but do not promise to be large sources of cash. Figure 16 shows the BCG portfolio and the norm strategies, which are related to each class. 3.2.2 Sharp Classification and Disadvantages Considered sharply, for example SBU 2 in Figure 17a, belongs only to one class, C1 (stars). Following the norm strategy (of Figure 16b), the SBU 2 is may be managed in the same way as the real star, SBU 1. This could be problematic since the performance (growth and market share) of SBU 2 still can be improved. The same classification problem occurs to SBU 3, which is sharply classified as a poor dog (C4), like weak SBU 4. However, this is not right, because SBU 3 is nearly in the same position as SBU 2 and is rather a star then a dog. Even if more classes are defined: sharp classification does not solve the problem that elements located near the borders of the classes are classified discriminatorily and imprecisely. . SBU 1 C4) . Poor dogs SBU 3 . SBU 2 C3) Cash cows SBU 4 Low High Relative market share . Real market growth C2) C1) 31% Question marks 0.9 0.1 6.6% Poor dog 24.2% Question mark . 0.48 0.42 C4) . Sharply classified sales, turnover or profit of a product, customer or SBU/SBF of the last year or average for recent years . . SBU 1 48.4% Star 14% Cash cow 20.4% Star 100% Poor dog SBU 4 00 0.44 0.56 1 μ low market share Figure 17: Sharp (a) and Fuzzy (b) BCG Portfolio - 26 - SBU 2 C3) 25.6% SBU 3 Cash cow 29.8% Poor dog 1 Fuzzy classified sales, turnover or profit 100% Star 0.3 0.7 μ high market share Relative market share C1) Stars High C2) Question marks μ low market growth μ high market growth b) Real market growth Low a) Chapter 3: Fuzzy Classification Management Tools 3.2.3 Fuzzy Classification and Advantages With fuzzy classification, misclassifications can be eliminated. Viewed through a fuzzy lens (Figure 17b), SBU 2 belongs now to all classes at the same time with following normalised membership degrees: 48.4% to the class ‘stars’, 31% to ‘question marks’, 14% to ‘cash cows’ and 6.6% to the ‘poor dog’ class. SBU 3 goes also with all classes (20.4% ‘star’, 24.2% ‘question mark’, 25.6% ‘cash cow’, 29.8% ‘poor dog’) and can be separated from the real dog SBU 4 and managed accordingly. Considered sharply, there is no ‘question mark’ in the portfolio to invest. Classified fuzzily, there is a certain percentage; with the fCQL toolkit, the membership degrees of all the classified business units to the class C2 (‘question marks’) can be queried: classify from with SBU portfolio class is question marks In this simple example with four SBU’s, the user will receive following absolute membership degrees to C2: SBU 2: 50.1% and SBU 3: 41.9%. The portfolio manager now wants to find out which businesses are performing well, i.e. all membership degrees of all fuzzy classified SBUs to the class ‘stars’ (C1). He queries: classify from with SBU portfolio class is stars By querying the following membership functions, he obtains the same results: classify from with SBU portfolio real market growth is high market growth and relative market share is high market share In this example the query results are also obvious (absolute degrees; SBU 1: 100%, SBU 2: 78.2%, SBU 3, 35.3%). However, in business practice, where portfolios of an enterprise may consist of hundreds of businesses or products, the query process and the results are more complicated. In this case, the potential and the benefit of the fCQL toolkit is much higher. Applying fuzzy classification to strategic portfolios has several implications. Fuzzy classification allow portfolio managers to analyse and decide differentiated and more precisely about actual and future strategies of each classified business unit. Since the membership degrees to the different classes, e.g. all membership degrees of all fuzzy classified businesses to the class C2, can be exactly calculated, the degree of investments in businesses can be undertaken proportionally to the share to a class. Figure 18 shows an example of such fuzzy investment. Since ‘question marks’ have to gain in market share, they require the highest capital spending proportion, for instance 60 percent of the investment expenditures. In addition, ‘stars’ (C1: medium investment of 30%) and ‘cash cows’ (C3: low investment 10%) need some investments to hold the market share. There are no investments in ‘poor dogs’ (C4: 0%). - 27 - Chapter 3: Fuzzy Classification Management Tools SBU 2 SBU 3 SHARPINV3 = 60% High investment (60%) SBU 5 Low C4) SBU 1 Medium investment (30%) SHARPINV4 = 30% SBU 4 C3) No investment Low investment (0%) SBU 7 (10%) SHARPINV7 SBU 6 = 0% SHARPINV = 10% 6 SBU 8 SHARPINV8 = 0% Low FUZZINV2 = 48.1% C1) SHARPINV5 = 10% High Real market growth C2) SBU 2 SBU 3 FUZZINV3 = 60% 1 0 SBU 1 FUZZINV1 = 30% 26.1% medium investment 17.3% high investment 33.3% low investment 23.3% no investment FUZZINV5 = 0.261·30 + 0.173·60 + 0.333·10 + 0.233·0 = 21.5% SBU 8 C1) FUZZINV4 = 26.2% SBU 4 SBU 5 C3) SBU 6 SBU 7 FUZZINV7 = 4.7% FUZZINV6 = 10% FUZZINV8 = 0% Relative market share High C2) b) SHARPINV1 = 30% SHARPINV2 = 60% μ low market growth μ high market growth Real market growth Relative market share a) 0 SHARPINVi = Sharp investment in SBUi (i = 1,…,8) 1 FUZZINVi = Fuzzy investment in SBUi (i = 1,…,8) μ low market share μ high market share Figure 18: Sharp (a) and Fuzzy (b) Investments Classified sharply (Figure 18a), 60% are invested in both SBU 2 and SBU 3. However, in the fuzzy classified portfolio (Figure 18b), the investment in SBU 2 amounts only 48.1%, not 60% anymore. Sharply, SBU 5 in the middle of the portfolio belongs only to class C3) with 10% investment. Fuzzily, in SBU 5 is invested much more: 21.5% (for calculation see Appendix 1). In contrast to sharp portfolio analysis, fuzzy one enables to calculate a theoretically most efficient investment and an optimal allocation of limited resources. However, these values have to be considered as benchmarks for the share to be invested. The exact sum for the investment depends on what is necessary for the development of the business or the SBU. Considered dynamically, fuzzy portfolio analysis enables to monitor the development or investments in each business unit and its performance over time. In addition, fuzzy classification contributes to the achievement of a main objective of portfolio analysis: a well-balanced collection of investments. Fuzzy portfolio analysis facilitates to balance mature cash producing business units and future-oriented units, which require investments. This ensures, on the one hand, that the company is investing in markets, which are highly attractive in the future, and on the other hand, that the business units in mature markets must be self-financing and produce free cash flow, which can be invested in other business units [Grant 2002, p. 410]. To balance a portfolio, management has first to define an ideal composition of the portfolio, the optimal percentages of the normalised membership degrees of all classified business units to each class. In Figure 19c), an optimally Balanced Portfolio (BP*k; symbol: ;) consists of 33% membership degrees of all business units to class C1 (BP*1 = ∑Mnorm(Oi│C1) = 0.33), 21% membership degrees of all business units to class C2 (BP*2 = ∑Mnorm(Oi│C2) = 0.21), 37% membership degrees of all business units to class C3 (BP*3 = ∑Mnorm(Oi│C3) = 0.37) and at most 09% membership degrees of all business units to class C4 (BP*4 = ∑Mnorm(Oi│C4) = 0.09). In this case, the ‘cash cows’ and ‘stars’ generate enough free cash flows, which can be invested in ‘question marks’, i.e. in the future of the company. - 28 - Chapter 3: Fuzzy Classification Management Tools If the portfolio is optimally balanced (BP*k), the Balance Error (BE) is 0. The higher the sum of the absolute deviations (│absolute values│) between the membership degrees Mnorm(Oi│Ck) and the degrees of an optimally balanced portfolio, the higher is the balance error. ⎛ n ⎞ ⎛ n ⎞ ⎛ n ⎞ ⎛ n ⎞ BE = ⎜ ∑Mnorm(Oi C1 ) − 0.33⎟ + ⎜ ∑Mnorm(Oi C2 ) − 0.21⎟ + ⎜ ∑Mnorm(Oi C3 ) − 0.37⎟ + ⎜ ∑Mnorm(Oi C4 ) − 0.09⎟ ⎝ i =1 ⎠ ⎝ i =1 ⎠ ⎝ i =1 ⎠ ⎝ i =1 ⎠ Example of C4 in Figure 19b/d: │.25-.33│+│.22-.21│+│.14-.37│+│.39-.09│ = .08 + .01 + .23 + .3 = 0.65 In addition to the BE, basic requirements should be defined for an optimal portfolio, e. g. not less ‘cash cows’ than 25% of the portfolio (∑Mnorm(Oi│C3) > 0.25), at least 10% ‘questions marks’ (∑Mnorm(Oi│C1) > 0.1) or not more ‘poor dogs’ than 15% (∑Mnorm(Oi│C4) < 0.15). a) Unbalanced Portfolios b) Balance Indicator Future cash flow C3-4) C3-3) : : Optimally balanced portfolio Unbalanced customer portfolios Trigger mechanism (red-flag-function) 0.4 0.37 0.35 0.36 0.39 0.25 C4-3) C4-4) 0.37 0.54 0.22 0.14 0.30 Share 0.1 C1) actual cash flow Balanced (diversified) portfolio C4) C3) Insufficient actual & future cash flow Insufficient future potential : Real market growth C1-1) C1-2) Stars: 33% Question Marks: 21% BP*1 = ∑Mnorm(Oi│C1) = 0.33 0.21 max.: 0.18 ; C2) : 0.65 0.64 0.33 0.19 0.05 :Insufficient Portfolio with both insufficient actual & future cash flow Portfolio with insufficient future potential Portfolio with insufficient actual cash flow C4-1) Actual cash flow : : C4-2) Relative market share C2-3) C3-1) Relative market share C2-4) C3-2) Relative market share C2-1) C2-2) C1-4) C1-3) Poor Dogs: 9% Cash Cows: 37% 0.09 0 Relative market share Real market growth Real market growth Balance error (BE) Market growth CX.1 Stars CX.2 Question marks CX.3 Cash cows CX.4 Poor dogs d) Balance Error and Implementation of a Trigger Mechanism c) Optimally Balanced Portfolio (BP*k) Figure 19: Balancing of Fuzzy Classified Portfolios If there are too little membership degrees of all classified businesses to class C2-3 (portfolio with insufficient actual cash flow in Figure 19a), to class C3-2 (portfolio with insufficient future potential) or to C4-2 and C4-3 (portfolio with both insufficient actual and future cash flow), the portfolio is not balanced (symbol: :). In this case, the basic requirements are not fulfilled and/or the level of the balance error exceeds the maximum level (max. of 0.30 in Figure 19d). A trigger mechanism (red-flag-function) warns the portfolio manager who can launch counter measures to augment actual cash flow or/and future cash flows, by investing in R&D or by acquiring new businesses in order to balance and optimise the composition of the portfolio. - 29 - Chapter 3: Fuzzy Classification Management Tools The fuzzy portfolio analysis approach is not only promising for the BCG portfolio, but can be applied to all other existing portfolio analyses. For instance, the more complex McKinsey/ General Electrics portfolio holds the dimensions ‘industry attractiveness’ and ‘competitive strength’, which can be defined by one or several criteria shown in Table 6. Table 6: Criteria for Assessing Industry Attractiveness and Competitive Strength W Criteria for assessing industry attractiveness Criteria for assessing competitive strength Industry or market size or volume Industry or market growth or potential Industry or market profitability Capital, investment or cost intensity Technological level and stability Innovation intensity and potential Competitive intensity or entrance barriers Cyclical, seasonal or inflation independence Dependence of regulation and government Risks (industry, technology, environment, etc.) Market share or growth of market share Corporate size and financial strength Market, customer or technological knowledge Product quality Corporate or product image Production, sales or service effectiveness Low operating costs and productivity Price competitiveness Distribution network or geographic advantages Competence of management and employees Source: adapted from [Kotler et al. 2005, p. 62, Grünig and Kühn 2005b, p. 176, Waibel an Käppeli 2006, pp. 85f] The two attributes ‘industry attractiveness’ and ‘competitive strength’ with the terms ‘low’, ‘medium’ and ‘high’ define nine squares (classes C1 to C9 in Figure 20a). To each class in the industry attractiveness/competitive strength portfolio, general recommendations for strategies are assigned: the strategy ‘growth/investment’ (invest and tolerate any negative free cash flow), ‘selective’ and ‘harvest/divestment’ (invest a minimum, divest if cash flow is negative). Keeping strictly to these norm strategies could be problematic, as following examples show. Although SBU 2 is almost in the same position as SBU 1, it is in a red field and may wrongly disinvested, but in green SBU 1 is invested. In SBU 3 it also divested, although it is not in such a bad position as SBU 4 and a selective strategy would be appropriate. With fuzzy classification and the disappearance of the classes sharp borders (Figure 20b), the problems are solved; it can be fuzzily invested or disinvested in businesses for optimal growth. b) Double Try or quit SBU 1 harder SBU 2 Proceed Selected with care withdrawal C7) Low C9) C5) C8) SBU 3 Phased Divest withdrawal SBU 4 Low Medium C1) Leader C2) Growth C6) Cash Generation High Source: [Schawel and Billing 2004, p.147] Competitive strength High C3) Medium C4) 1 0 Growth/investment strategy C4) C3) C1) Double or quit Try harder Leader C7) C5) C2) Selected withdrawal Proceed with care Growth C9) C8) C6) Divest Phased withdrawal Cash Generation Competitive strength Industry attractiveness Industry attractiveness μ unattractive μ medium attractive μ attractive a) Sharp classification 0 Selective strategy 1 Harvest/divestment strategy μ low competitive μ medium competitive μ high competitive Figure 20: Sharp (a) and Fuzzy Classified (b) McKinsey/General Electrics Portfolio - 30 - Chapter 3: Fuzzy Classification Management Tools 3.3 Fuzzy SWOT Analysis 3.3.1 Definition SWOT stands for Strengths, Weaknesses, Opportunities and Threats and is an often used strategic analysis and planning method both in business management theory and practice. According to [Kotler et al. 2005, pp. 58f], SWOT analysis is “a distillation of the findings of the internal and external audits which draws attention to the critical organisational strengths and weaknesses and the opportunities and threats facing the company.” The strengths and weaknesses analysis is an internal audit that focuses on the corporate performance, strategy, resources, capabilities or developments. For instance, the following elements can be classified: company’s sales, materials, production, products, services, customers, financial resources, employees and skills, know-how, innovative ability or flexibility. The opportunities and threats analysis is carried out by examining external elements of the demographic, economic, political, legal, sociological, technological or cultural environment and of competitors (e.g. their products, prices, distribution, resources or customers). b) Weaknesses Convert Reduce Opportunities Threats C4) C3) Positive Negative Strengths C1) Element 1 Weaknesses Element 3 C4) 1 Element 4 Opportunities μ external Reduce Evaluation External Convert Element 2 C3) Threats Element 5 0 Evaluation Strengths C2) Avoid C1) Match C2) Perspective μ internal Perspective Internal a) 0 1 μ positive μ negative Figure 21: Sharp (a) and Fuzzy (b) SWOT Matrix 3.3.2 Sharp Classification and Disadvantages So far, the SWOT analysis has been applied in a sharp manner in most cases: the elements or attributes in the SWOT are classified sharply, i.e. an attribute is classified exactly and only to one class (to C1, C2, C3 or to C4 in Figure 21a). In fact, in SWOT dominates a "negative-or-positive-" and a "internal-or-external-thinking". However, it is often inadequate to classify objects sharply, as Figure 21b shows: - 31 - Chapter 3: Fuzzy Classification Management Tools Elements 1 and 2 are considered as weaknesses. However, element 2 was evaluated not as negative as 1 and should be viewed as positive too, as a weakness and as a strength. Although element 3 and 4 are located nearly at the same position, they sharply belong to different, opposite classes: element 3 is internal and negative, 4 external and positive. Even though element 4 and 5 are both classified in the same class C4, their positions are actually very different. While element 5 is certainly a high opportunity, for 4 this is not clear: it could quickly change into strength, weakness or into a threat. 3.3.3 Fuzzy Classification and Advantages As these examples point out: it makes sense to consider transitions between different classes step like. With a fuzzy SWOT analysis (Figure 21b), the classification problem can be avoided, since the classified elements can be partly internal, external, positive and negative at the same time. This reflects reality better, since it is rarely the case that a classified element, characteristic, object or fact has only positive or only negative points. Fuzzy classification not Degree of strength Degree of weakness (competitive advantages or KPIs or KSF to retain) C2-4) C2-3) Unimportant strengths Development strengths (to keep or to selectively improve) (to improve) 1 0 1 μ unimportant C2) C1) Strengths Weaknesses C4) C3) Opportunities Threats 0 C4-4) C4-3) Negligible opportunities Limited opportunities (to ignore) (to improve attractiveness ) 0 1 μ very improbably μ very probably μ very serious (to focus on and to invest) analogue: Damage C3-2) High risks C3-1) Extreme risks C3-4) Low risks C3-3) Moderate risks Fuzzy Risk Matrix μ not serious (to improve success probability) 1 Probability 0 C4-1) High opportunities (to keep low) (to monitor and selectively reduce) μ unimportant μ very important Seriousness of threat Success probability μ very attractive μ unattractive 1 C4-2) C1-3) Secondary weaknesses d) Fuzzy Threat Matrix Attractiveness of opportunity Golden opportunities C1-4) Unimportant weaknesses 0 1 μ very important c) Fuzzy Opportunity Matrix C1-1) Primary weaknesses (to monitor & reduce (competitive disadif necessary) vanteges to reduce) μ low weakness (to selectively retain) C1-2) Irrelevant weaknesses 0 C3-2) C3-1) Latent but high threats Major threats (to monitor; e.g. emergency planning) (to pay high attention and to avoid by contingency plan- C3-4) C3-3) Minor threats Probable but low threats (to ignore) (to monitor and to avoid if necessary) 0 1 μ very improbably μ very probably Figure 22: Fuzzy Strength (a), Weakness (b), Opportunity (c) and Threat (d) Matrices - 32 - Probability of occurrence 0 C2-1) Strategic strengths Importance of strength μ low strength 1 C2-2) Ineffectual strengths μ high weakness b) Fuzzy Weakness Matrix μ high strength a) Fuzzy Strength Matrix Importance of weakness can be applied to the SWOT matrix only, but also to each of the four classes in Figure 22. Chapter 3: Fuzzy Classification Management Tools Each strength of the fuzzy strength matrix (Figure 22a) can be evaluated fuzzily by its degree of importance, whether it is rather a ‘strategic strength’ (a Key Success Factors; KSF), an ‘ineffectual’, an ‘unimportant’ or a ‘development strength’ to improve. Management can acquire information on all ‘strategic strengths’ by querying the membership degrees to C2-1: classify from with strengths strength matrix class is strategic strengths Appendix 2 (Checklist for Performing; Fuzzy Strengths/Weaknesses Analysis) shows a list, how marketing, finance, manufactering or organisation performance can be evaluated fuzzily. Management also needs to monitor key macroenvironment forces (demographic-economic, natural, technological, political-legal, and social-cultural) and significant microenvironment actors (customers, competitors, suppliers, distributors, dealers) that affect its ability to earn profits. For each development or trend of the external environment, management has to identify the associated opportunities and threats [Kotler and Keller 2005, p. 52]. To evaluate opportunities, the manager can use a Market Opportunity Analysis (MOA) to determine the attractiveness and probability of success, by defining a fuzzy opportunity matrix (see Figure 22c). To determine fuzzily the best marketing opportunities to invest (C4-1), the user queries: classify from with opportunities opportunity matrix class is high opportunities In addition, threats have to be observed as well: an environmental threat is a challenge posed by an unfavourable trend or development that would lead, in the absence of defensive marketing action, to lower sales or profit [Kotler and Keller 2005, p. 53]. Threats should be classified according to their seriousness and their probability of occurrence (fuzzy threat matrix in Figure 22d). Analogical to the threat matrix, a risk matrix classifies different risks by their ‘amount of damage’ and the ‘probability of occurrence’. The risk map is an important instrument to analyse, evaluate and to classify potential risks for a division, a business unit or for the whole company. The ‘probability of occurrence’ can be estimated either quantitatively on a metric scale, or qualitatively on an ordinal scale from ‘very improbably’ (rare likelihood of risk occurrence) to ‘very probably’ (risk occurs almost certain), and the ‘amount of damage’ from ‘insignificant’ to ‘catastrophic’. As shown in Figure 23a, the classes C1 to C25 are assigned to four different level of risk: low, moderate, high and extreme. Risks classified above the threshold (dashed diagonal) have to be surveyed exactly. A risk manager can follow different strategies to accept, retain or limit, reduce, avoid or to transfer risks to third parties (i.e. to assurances). So far, the risk matrix has been applied in a sharp manner, although this can be problematic as the examples in Figure 23a show: risk A and B are nearly in the same position, but they are classified in very different classes: risk A is a low risk to accept and B is a high risk to reduce. - 33 - Chapter 3: Fuzzy Classification Management Tools Amount of damage C20) Z C4) C2) C12) C8) C5) C13) Risk C C9) C6) C14) C10) C17) C1) X C3) Risk D Y a C23) \ C25) Very low C21) Risk B C18) Risk A [ C24) Low C22) C19) Medium High High risk to transfer or to reduce Low risk to accept or to retain μ catastropic C16) C7) ] C15) Very high μ insignificant C11) Probability of occurrence insignificant minor moderate major catastropic b) Threshold of risk 1 Extreme risk to avoid or to transfer Moderate risk to reduce or to accept 0 C1) Improbable risks with high amount of damage Probable risks with high amount of damage C4) C3) Improbable risks with low amount of damage Probable risks with low amount of damage 0 1 Examples of risks: C2) Probability of occurrence a) Amount of damage μ very probably μ very improbably Source of examples: [Gladen 2006, p. 130] X Market risk Y Natural disasters Z Contractual risk [ Personell risk \ Legal risk ] Production risk Figure 23: Sharp (a) and Fuzzy (b) Risk Matrix Risk C and D, one the other hand, are classified in the same class, although the amount of damage and the probability of occurrence of risk D is higher. With fuzzy classification (Figure 23b), such mistakes do not happen and risks of the matrix can be classified, managed and controlled more exactly. To receive the membership degrees of all risks, where the amount of damage is catastrophic and the probability of occurrence is very high (C1), it has to be queried: classify from with risks risk matrix probability of occurrence is very probably and amount of damage is catastropic This section illustrated that the use of a fuzzy SWOT analysis is manifold. It enables a more exactly and differentiated description of the classified elements in all matrices to discern new market and marketing opportunities to classify and survey different kind of threats or risks in the fuzzy risks matrix the analysis of the company’s prospects for sales and profitability to focus on the corporate activities and resources to improve deficiencies and shortcomings and to defend or to extend strengths to reveal the real core competences or competitive advantages, and disadvantages the identification of Key Performance Indicators (KPI) or Key Success Factors (KSF) the formulation or adoption of corporate, business or marketing strategies a clear semantic and a reduction of redundant internal classes to monitor the SWOT matrices or the risk matrix dynamically and fuzzily over time the definition of a strength, weakness, opportunity or threat and a SWOT indicator and the implementation of trigger mechanisms, if SWOT or risk indicators are degrading. - 34 - Chapter 3: Fuzzy Classification Management Tools 3.4 Fuzzy ABC Analysis 3.4.1 Definition The ABC analysis is the most widely used method of customer, material or product segmentation. In CRM practice, the ABC analysis is used between 29% and 88% of all companies, depending on industry and study (see e.g. [Plinke 1997, Rudolf-Sipötz 2001, Köhler 2005, Bruhn and Georgi 2006, Günter and Helm 2006, Reinecke and Tomczak 2006, Homburg and Krohmer 2006]). ABC analysis is used to reduce complexity, to analyse and monitor the customer structure, and to prioritise investments. It classifies customers into three different segments, into A-, B- and C-customer. In Table 7, 20 customers are sorted by their turnover. Table 7: Sharp ABC Analysis # Cumulative share of customers (%) 1 2 3 4 5 6 7 8 … 19 20 5% 10% 15% 20% 25% 30% 35% 40% … 95% 100% Class Class def. Number of Customer (sharp) Customers A [0,…,11.9] B [12,…,35.9] 5 C [36,…,100] 13 2 Marshall Miller Brown Wright O’Connor Cooper Smith Ford … Graham Forrester Total Turnover 2006 (€) 21’760 19’040 9’520 4’080 3’400 2’040 1’224 816 … 408 340 68’000 Cumulative Turnover (%) 32% 60% 74% 80% 85% 88% 89.8% 91% … 99.5% 100% "20:80rule" The cumulative shares show, how many customers generate how much of the turnover. In CRM literature (for instance [Homburg and Beutin 2006, p. 230]), often the 20:80-rule, or the Pareto-rule is mentioned, which states that 20% of the customers generate 80% of the turnover. Usually, very few A-customers have a high value percentage. In Table 7, only two Acustomers, Marshall and Miller, generate 60% of the turnover. The B segment has a medium value and a majority of the customers (C) have a low share in turnover. The Lorenz or concentration curve in the example of Figure 24 indicates a concentrated distribution of customer turnover. In the case of an equipartition, the curve would be a diagonal. 3.4.2 Sharp Classification and Disadvantages So far, the rather uncritical discussion about ABC analysis for customer segmentation in literature on marketing is always done in a sharp way. However, it is problematic to classify customers sharply. First, the definition and fixing of the three classes (A: [0,…,11.9], B: [12,…,35.9] and C: [36,…,100] in Table 7) is arbitrary. Second, sharp classification can be unfair and lead to wrong decisions as the examples of the four customers in Figure 24 show: - 35 - Chapter 3: Fuzzy Classification Management Tools Although Ford and Smith have similar turnovers, Ford is classified to class C and Smith to B. Even though Brown’s turnover (9’520 €) is totally different from that of Smith (1’224 €), they belong to same class B. However, Brown is rather an A-customer like Miller and should be considered as a key account too. If Brown or Ford had little higher turnover, in some cases may be only a few euros, they would slip into a higher class and were managed differently. 3.4.3 Fuzzy Classification and Advantages Cumulative turnover (%) #6 90% #4 80% #7 Sharp ABC Analysis #10 #8 #9 #5 #20 #15 #16 #17 #18 #19 #11 #12 #13 #14 Lorenz curve (concentration curve) #3 70% #2 60% 50% Cumulative turnover (%) B-customers A-customers C-customers Ford Smith Cumulative share of customers (%) 100% Brown #1 40% Miller 30% “20:80-Rule” 20% A-customers B-customers 10% C-customers 0% 0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100% 0 1 0 μA μB 1 μC Cumulative share of customers (%) With fuzzy classification, the transitions between A-, B- and C-customers became fluent. Figure 24: Fuzzy ABC Analysis With fuzzy classification, the transitions between A-, B- and C-customers' become fluent and customers can be fuzzily classified by their real turnover (compare Figure 24 and Table 8). Considered fuzzily, only Customer #1 is an A-, #5 a B-, and #10-20 are C-customers only. For the rest a membership degree for both classes [A and B] or [B and C] are calculated. Table 8: Fuzzy ABC Analysis # Cumulative share of customers (%) 1 2 3 4 5 6 7 8 9 … 19 20 5% 10% 15% 20% 25% 30% 35% 40% 45% … 95% 100% Class A (A, B) B (B, C) C Class definition (fuzzy) ([A: 100%]) ([A: 64%], [B: 36%]) ([A: 32%], [B: 68%]) ([A: 6%], [B: 94%]) ([B: 100%]) ([B: 74%], [C: 26%]) ([B: 57%], [C: 43%]) ([B: 38%], [C: 62%]) ([B: 10%], [C: 90%]) ([C: 100%]) - 36 - Customer Marshall Miller Brown Wright O’Connor Cooper Smith Ford Spencer … Graham Forrester Total Turnover 2006 (in €) 21’760 19’040 9’520 4’080 3’400 2’040 1’224 816 748 … 408 340 68’000 Cumulative turnover (%) 32% 60% 74% 80% 85% 88% 89.8% 91% 92.1% … 99.5% 100% Chapter 3: Fuzzy Classification Management Tools Another restriction of the discussed example of ABC analysis is the isolated consideration of only one single criterion, turnover. Customer turnover provides no information about the costs and the profitability of a customer. Consequently, a differentiated fuzzy ABC analysis should consider different customer performance indicators for profitability and investments (Figure 25a), for example customer contribution margins, net profit or the Return on Customer (ROC). CRM should not consider financial metrics only, but also qualitative indicators about the customer relationship, i.e. a fuzzy ABC analysis of customers’ satisfaction, loyalty or retention (Figure 25b). In this case, very (dis)satisfied or (dis)loyal customers are identified. In addition, even a highly unprofitable C-customer can be important for a company, since he may has a very good recommendation, information or cooperation behaviour (Figure 25c), e.g. a high number of recommendations and suggestions, or profound product knowledge. 0 μA μB μC Fuzzy ABC analysis of customer relationship A-customers B-customers C-customers 0 0 1 1 μA μB μC Performance measure of recommendation, information & cooperation (I151-173) Fuzzy ABC analysis of customer recommendation, information & cooperation A-customers B-customers C-customers 0 0 1 1 Cumulative share of customers A-customers B-customers C-customers Customer performance measure of relationship (I111-150) Cumulative share of customers Cumulative share of customers Fuzzy ABC analysis of customer revenue, profitability & investment 1 c) b) a) Customer performance measure of profitability & investments (I1-110) 0 μA μB μC 1 Examples of customer performance Examples of customer relationship Examples of customer recommendation I# I# indicators for revenue & profitability indicators information or cooperation indicators I21 Demanded volume I124 Customer value I152 Number of recommendations I39-41 Share of wallet or customer I130 Customer involvement I155 Potential reference recipients I50-53 Cross-/up-selling I131 Customer commitment I156 Role as opinion leader I55,56 Repurchases I132 Customer attachment I158 Consulting/helpdesk intensity I69-74 Contribution margins I-IV I133 Customer trust I163 Number/quality of suggestions I75-78 Customer gross/net profit I126 Customer satisfaction I164 Number of complaints I79 Customer equity I134 Customer loyalty I167 Number of returns I80,81 Customer Lifetime Value I137 Customer retention I168 Product expertise or knowledge I83-85 Customer potential I147 Duration of customer relationship I169 Response rate I102 Total customer costs I148 Intensity of customer relationship I171 Cooperation behaviour I104 Return on customer (ROC) I149 Quality of relationship I172 Expertise for cooperation For Detail on customer performance indicators (I 1 - I 173) see Appendix 4: 170+ Customer Performance Indicators (pp. 136ff) I# Figure 25: Fuzzy ABC Analysis with Different Customer Performance Indicators As these examples point out: a fuzzy ABC analysis can be adapted with any kind of criteria or indicators. In addition, the fuzzy ABC analysis can be combined with other analysis methods, for instance with the fuzzy portfolio analysis. The combination of the fuzzy ABC analysis with the customer attractiveness/competitive position portfolio (discussed in Chapter 2) defines a fuzzy classification space with six classes, C1 to C6 in Figure 26. ‘A-star-customers to maintain’ (C1) are customers with a high degree of attractiveness, e.g. customers with high potential for future turnover or customer lifetime value, and with a strong competitive position (e.g. customers with a high share of wallet). - 37 - Chapter 3: Fuzzy Classification Management Tools Customer attractiveness (or potential) Customer attractiveness (or potential) C1) C-development- B-development A-starcustomers customers customers (to invest) (to invest) (to maintain) μ unpromising C6) C4) C2) C-renunciation- B-absorption- A-absorptioncustomers customers customers (not to invest) (to skim) (to skim) 1 0 0 1 μ weak (C) μ medium (B) C2) C4) μ strong (A) Ford C6) Acquisition strategies Recovery strategies Consequent implementation C1) Competitive Position C3) Competitive position μ promising Miller C5) Brown Smith C5) C3) Penetration strategies Disinvestment strategies Moderate implementation Retention strategies Moderate & aligned strategies Figure 26: Combination of the Fuzzy Portfolio and ABC Analysis ‘A-absorption-customers’ in C2 are ‘strong’ too, but their attractiveness is lower than in C1. In ‘B-development-customers’ (C3) has to be invested, but unpromising ‘B-absorption-customers’ (C4) are rather to skim, like those of C2. A ‘C-development-customer’ (C5) is still promising. In contrast, ‘C-renunciation-customers’ (C6) are less attractive and should not be invested in. Considered sharply, customer Ford in the example belongs entirely to C6 and would not be invested in; fuzzily she belongs to four classes (C2, C4, C5, C6) and is part of different strategies. Customer Smith and Brown also belong to four classes. Miller belongs to C1 and to C2, i.e. he is not a 100%-A-star-customer anymore: his ‘competitive position’ still can be improved. This combination of the fuzzy portfolio and ABC analysis is an interesting method for the formulation and implementation of customer strategies. According to the corporate positioning in the market, to the target segment and to the customer acquisition strategy, a company has to acquire new, promising customers to maintain or increase sales, profits and market share. To develop C- or B-customers, the company has to define and implement development and penetration strategies to intensify customer relationships and to strengthen the company’s competitive position at the customers. This can be realised e.g. by cross-/up-selling strategies or by increasing purchase frequency and intensity. In addition, the company should augment customer retention by different marketing actions discussed in Chapter 4. The intensity of the strategy implementations has to vary according to the level of a customer’s attractiveness. With the simultaneous consideration of quantitative and qualitative criteria, the fuzzy ABC analysis segments customers differentiated, fairly and non-discriminatory. CRM can treat the customers according to their value for the company. As a result, strategic and operational decisions about customers or customer segments (e.g. key accounts), can be enhanced. Finally, the fuzzy portfolio and ABC analysis enables an improved personalisation, individualisation and differentiation of the products and services and better mass customisation. - 38 - Chapter 3: Fuzzy Classification Management Tools 3.5 Fuzzy Scoring Methods 3.5.1 Definition In contrast to the ABC and portfolio analysis, which consider only one or two criteria, with scoring methods several quantitative or qualitative variables can be taken into account. The scoring approach assigns a predefined, weighted score to each value of a customer variable. All scores of the different variables are added to the customer’s total score. The most well-known example of a scoring method is the so called RFM method. RFM stands for ‘Recency of last purchase’, ‘Frequency of last purchase’ and ‘Monetary value’ and is a widely accepted and often used measurement tool in direct marketing and CRM (see for instance [Link and Hildebrand 1993, Blattberg et al. 2001, Köhler 2005, Homburg and Sieben 2003, Neckel and Knobloch 2005, Günter and Helm 2006, Bauer et al. 2006, Krafft 2007]). Empirical analyses show significant correlations between these three variables and the repurchase behaviour of customers, e.g. the response rate to mailings [Köhler 2005, Krafft 2007]. High frequencies and high monetary values of customer repurchases are more likely the more recent a customer purchased (recency) the more frequent a customer ordered in defined period (frequency) and the higher customer turnovers were in the last years (monetary value). 3.5.2 Sharp Classification and Disadvantages The more recent and frequent a customer purchased products from the company in a period, and the higher the monetary value is, the more the points assigned to a customer. Table 9 shows an example of the RFM method used in mail order business. The assignment of the points to the classes obviously happens in a sharp manner. If a customer ordered for 99 €, for instance, he is classified sharply in the Monetary class ‘51-100 €’ and receives plus 25 points. Table 9: Example of the RFM Method with Sharp Classes Variables Initial score Date of last purchase (Recency) Number of orders (Frequency) Ø turnover of last 3 orders (Monetary) Number of returns Number of mailings since last purchase Customers Points per variable +25 ≤ 6 months: +40 7-9 months: 10-12 months: 13-18 months: 19-24 months: earlier: +25 +15 +5 -5 -15 Number of orders or purchases multiplied by 6 ≤ 25 €: +5 26-50 €: +15 0-1: 2-3: 0 -5 Per main catalogue: -12 51-100 €: +25 101-150 €: +35 4-6: 7-10: -10 -20 Per special catalogue: -6 151-200 €: +40 >200 €: +45 11-15: -30 Per mailing: -2 >15: -40 Brown Miller +25 +25 28 weeks: 27 weeks: +25 +40 7·6 = +42 7·6 = +42 99 €: +25 102 €: +35 0: 0 1 mailing: -2 Total score 115 0: 0 1 mailing: -2 140 Source: adapted from [Link and Hildebrand 1993, p. 49, Neckel and Knobloch 2005, p. 211] - 39 - Chapter 3: Fuzzy Classification Management Tools However, this frequently used RFM model with sharp classes is very problematic. Customers Brown and Miller have the same values for four variables (see Table 9): both have an initial score of +25, the same number of orders (+42), returns (0) and mailings (-2). Nevertheless, there are two little differences: the date of Brown’s last purchase was 28 weeks ago (class: ‘7-9 months’), Miller’s last one was 27 weeks ago (class: ‘≤ 6 months’), and the average turnover of Miller (102 €; class: ‘101-150 €’) was 3 € higher than this one of Brown (99 €; class: ’51-100 €’). Since Miller ordered only one week earlier than Brown, and Miller only had a 3 € higher turnover, they are classified in two different classes and Miller (140 points) receives 25 points more than Brown (115 points). Although Miller and Brown had the same purchase behaviour, Miller had a 20% higher score than Brown and is may managed and treated differently by the mail order company. In addition, the opposite can happen too: although two customers have totally different purchase behaviour, they may have the same number of points. These examples show how imprecise and inadequate methods with sharp classes can be. 3.5.3 Fuzzy Classification and Advantages To derive a fuzzy Recency Frequency Monetary method, the following example of the RFM approach shall be considered. The attribute or linguistic variable ‘recency’ is described by the terms ‘long ago’ and ‘very recent’, the attribute ‘frequency’ by the terms ‘rare’ and ‘frequent’ and the third attribute, ‘monetary value’, is divided into the terms ‘low value’ and ‘high value’. The contexts of the three qualifying attributes can be defined as follows: The attribute domain of ‘recency’ is defined by [0, 730] days and is divided into the equivalence classes [0, 365] days for ‘very recent’ last repurchase and [366, 730] days for a repurchase which took places a ‘long (time) ago’. The domain of ‘frequency’, measured by the number of repurchases, is [0, 100] and has two equivalence classes: [0, 9] for ‘rare’ repurchases, and [10, 100] for ‘frequent’ ones. The domain of the third variable ‘monetary value’ is defined by [0, 200] euros of customer average turnover, divided into the equivalence classes [0, 99] euros for ‘low value’ and into an average turnover of [100, 200] euros, which is considered as ‘high value’. Table 10: RFM Method: Definition of Classes and Scores Class C1 C2 C3 C4 C5 C6 C7 C8 Recency [Days last purchase] [0, 365] [0, 365] [366, 730] [366, 730] [0, 365] [0, 365] [366, 730] [366, 730] RFM attributes, [equivalence classes] and (terms) Frequency Monetary value (Term) Very recent Very recent Long ago Long ago Very recent Very recent Long ago Long ago [# of purchases] [10, 100] [0, 9] [10, 100] [0, 9] [10, 100] [0, 9] [10, 100] [0, 9] (Term) Frequent Rare Frequent Rare Frequent Rare Frequent Rare - 40 - [Ø turnover] [0, 99] [0, 99] [0, 99] [0, 99] [100, 200] [100, 200] [100, 200] [100, 200] (Term) Low value Low value Low value Low value High value High value High value High value Scores 70 p 40 p 30 p 0p 100 p 60 p 50 p 20 p Chapter 3: Fuzzy Classification Management Tools In Table 10, eight classes (C1 to C8) are defined by the RFM attributes and terms. For each class, a number of points are defined: the more recent and frequent a customer purchases products and the higher the monetary value is, the more points are assigned to the customer. The four customers are now sharply RFM classified and receive following scores (Table 11): Table 11: Sharp RFM Scoring of Customers Customer Class Smith Ford Brown Miller C3 C4 C5 C5 RFM attributes, [values of the customers] and (terms) Recency Frequency Monetary value [Days last purch.] 378 723 342 14 (Term) Long ago Long ago Very recent Very recent [# of purch.] 11 7 13 38 (Term) Frequent Rare Frequent Frequent [Ø turnover] 92 12 117 193 Score (Term) Low value Low value High value High value 30 p 0p 100 p 100 p Here again, the same problem of sharp classification emerges: although Smith and Brown have quite similar values, they are classified in different classes and to Smith are assigned 70 points less. In contrast, Miller is classified with 100 points in the same class as Brown, although Miller’s performance is much better. By the definition of fuzzy sets and membership functions, the RFM classification space becomes fuzzy (compare Figure 27b). b) Fuzzy RFM Method Recency Monetary value C5) 100 p C1) 70 p C2) 40 p C7) 50 p C8) 20 p Smith high value C3) 30 p C4) 0 p low value rare Miller frequent Brown Smith Frequency μ very recent C6) 60 p 1 8.97 + 3.86 + 3.35 +0 + 17.52 + 8.06 + 7.70 + 2.35 Miller C5) 100 points = 51.8 points Brown μ lang ago long ago very recent Recency C1) C2) C3) C4) C5) C6) C7) C8) Monetary value a) Sharp RFM Method C3) 12.86 C4) + 0 C1) 10.43 C2) + 5.22 Smith C3) + 5.20 C4) + 0 C5) + 9.71 C6) + 5.02 C7) + 5.73 C8) + 1.99 = 43.3 points μ high value Ford μ low value = 12.9 points 0 0 Frequency Ford C5) 100 points C5) 100 points C3) 30 points C4) 0 points 1 μ rare μ frequent Figure 27: Sharp (a) and Fuzzy (b) RFM Method With fuzzy classification, the scores of the customers can be calculated more exactly and fairly (for the calculation see Table 12 and Appendix 1). Classified fuzzily, 43.3 points are assigned to Smith, what is better than the 30 points in the sharp classification. Ford is also classified better (sharp: 0; fuzzy: 12.9 points), whereas Brown (51.8 points) is classified much lower in comparison to the sharp classification (100 points). Only Miller, who performs as good as possible in ‘recency’, ‘frequency’ and ‘monetary value’, still has the same 100 points. - 41 - Chapter 3: Fuzzy Classification Management Tools Table 12: Fuzzy RFM Scoring of Customers Class C1 C2 C3 C4 C5 C6 C7 C8 Mnorm(Oi│Ck) Corresponding membership functions to each class μvery recent μvery recent μlong ago μlong ago μvery recent μvery recent μlong ago μlong ago μfrequent μrare μfrequent μrare μfrequent μrare μfrequent μrare Ford Fuzzy Calculated RFM Score Smith Brown 0 0.14902 μlow value 70 0 0.13051 μlow value 40 μlow value 30 0.42857 0.17340 0.57143 0.15235 μlow value 0 0 0.09708 μhigh value 100 0 0.08360 μhigh value 60 0 0.11456 μhigh value 50 0 0.09948 μhigh value 20 1 1 Total 0.12810 0.09641 0.11167 0.08296 0.17521 0.13437 0.15395 0.11732 1 Miller Ford 0 0 0 0 1 0 0 0 1 Smith Brown 0 0 12.86 0 0 0 0 0 10.43 5.22 5.20 0 9.71 5.02 5.73 1.99 8.97 3.86 3.35 0 17.52 8.06 7.70 2.35 Miller 0 0 0 0 100 0 0 0 12.86 43.3 51.81 100 The membership degrees to the different classes and the total score of the fuzzy RFM model can be considered as an important indicator, how likely a customer is to purchase again by the company and how loyal a customer is. According to the membership degrees to the different classes, the customer manager could define incentives to animate customers to buy again, to purchase more frequent by the company, and at a higher monetary value: Customers who have recently bought the company’s products (C1, C2, C5, and C6) might receive a thank-you letter or an e-mail for buying from the company and for the confidence shown. In addition, these mailings may contain personalised product recommendations or cross- and up-selling offers (like the e-mails from Amazon, for instance). To customers who bought or buy very frequently (C1, C3, C5, C7), the company should send mailings (e.g. catalogues) to inform about existing or new products and special offers. For customers with high monetary values a one-time discount is offered. The discount in percent (C5: 20%, C7: 10%, C6 and C1: 5%) also depends on the frequency and recency of purchases. Figure 28a shows the combination of the RFM incentives. C3) C4) C4) Smith C3) Ford frequent C7) Monetary value C8) rare C1) C1) high value low value Frequency C5) Low discount (5%) High discount (20%) 2 reminders 2 reminders 8 mailings per month 8 mailings per month C2) No discount (0%) 2 reminders 1 mailings per month C3) C7) Medium discount (10%) No discount (0%) 1 reminders 0 reminders 4 mailings per month 4 mailings per month C4) No discount (0%) 0 reminders 0 mailings Recency Smith Discount: 4.3% 1 reminders 4 mailings/month C6) Low discount (5%) 2 reminders 2 mailings per month Miller Discount: 20% 2 reminders 8 mailings/month 1 Brown Discount: 6.4% 2 reminders 4 mailings/month Ford Discount: 0% 0 reminders 1 mailings/month 0 0 Frequency C8) No discount (0%) 1 reminders 1 mailings per month 1 μ rare Figure 28: Fuzzy RFM Incentives - 42 - μ frequent Monetary value Smith Ford C2) C5) μ very recent C5) b) Fuzzy RFM Incentives Miller C6) μ lang ago C5) very recent Miller Brown Recency long ago a) Definition of RFM incentives μ high value μ low value Chapter 3: Fuzzy Classification Management Tools Classified sharply, Smith receives no discount, although he has similar values like Brown, who receives a high discount (20%). As a result, Smith may feel discriminated or betrayed by the company and he does his shopping elsewhere. Miller might feel the same way too, because he has the same discount as Brown, although his performance is much better than Brown’s. With fuzzy classification (Figure 28b), fair incentives can be offered and personal discounts calculated. Smith receives a discount of 4.3% (0.097·20 + 0.115·10 + 0.084·5 + 0.149·5) and Brown a discount of 6.4% (0.175·20 + 0.154·10 + 0.134·5 + 0.128·5). Miller still has the maximum of 20%. With personalised discounts the company offers the same incentives for all customers to repurchase by the company. In addition, Smith and Brown receive an adequate number of reminders according to their purchase behaviour and are informed about the company and its products. The service of a reminder or mailing should be based on permission marketing, so that customers are not annoyed about undesired information or advertising. Fuzzy scoring models in combination with a fuzzy hierarchical classification are not limited to three attributes, as discussed in this example of RFM analysis. By the assignment of weighted scores to any number of qualitative or quantitative criteria, scoring models can be applied flexibly and independently to different kinds of analyses in CRM. Both approaches, sharp and fuzzy scoring methods, are confronted with the same problem of weighting or assigning the "right" number of points to each class. Since the weighting of the classes’ score (e.g. C1: 70 points) is often done subjectively and intuitively, RFM methods are not as objective as they pretend to be. However, scoring and RFM methods are more valid, significant and objective, if certain valuation rules are considered (see [Plinke 1997, p. 140]). In addition, the weighting and scoring of the classes can be improved using empirical data and regression analyses (e.g. logistic regression). However, a fuzzy RFM analysis can be undertaken without knowing the optimal weights and scores: if the manager wants to know all clients who are most likely to repurchase, he queries: classify from with customers RFM recency is very recent and frequency is frequent and monetary value is high value This fuzzy classification query would return all absolute membership degrees of the customers to the class C5 (Ford: 0%, Smith 25.3%, Brown 45.7% and Miller 100%). With the fuzzy scoring approach, a company can identify, classify, analyse, score, profile, evaluate and segment customers and customer groups according to their value for the company (compare Section 5.1: Fuzzy Customer Segmentation with Important Indicators). In addition, fuzzy scoring and profiling of customers facilitates the selective communication to target customers or fuzzy segments, the adoption and customisation of the marketing mix and an effective management of customer relations. As a result, the allocation of limited ressources, like a marketing or CRM budget, can be optimised. - 43 - Chapter 4 Analytical Customer Relationship Management - 44 - Chapter 4: Analytical Customer Relationship Management 4.1 Customer Relationship Management (CRM) 4.1.1 Overview In Chapter 2, the fuzzy classification approach and fCQL (fuzzy Classification Query Language) were described and applied to different management tools in Chapter 3. This Chapter will now discuss the application of fuzzy classification and the fuzzy Classification Management Tools (fCMT) to the field of Customer Relationship Management (CRM). Fuzzy classification could be categorised as a multidimensional data analysis method. Consequently, the fuzzy classification approach with fCQL are especially suited for the different tasks and processes of analytical Customer Relationship Management (aCRM). However, it is a principal task of aCRM to analyse, classify, evaluate and segment customers and their performance according to their value for the company in order to manage and maximise customers like any other asset of the company [Blattberg et al. 2001]. That means: analytical customer relationship management needs a comprehensive and holistic Customer Performance Measurement (CPM; content of Section 4.2). To measure customer performance comprehensively, CPM has to define, collect, record and manage an adequate customer data and Customer Performance Indicators (CPI; discussed in Section 4.3). The fuzzy classification and evaluation of customer performance indicators is an important condition to fuzzily segment customers (content of Chapter 5) and to define and implement appropriate strategies for a customer or for a customer segment. These processes and the structure of Chapter 4, Analytical Customer Relationship Manage- Customer Performance Measurement (CPM) (Section 4.2) Customer Performance Indicators (CPI) (Section 4.3) applied to Management tools (fCMT) (Chapter 3) applied to Fuzzy classification (Chapter 2) Customer Relationship Management (CRM) (Section 4.1) Fuzzy customer performance analysis, classification and evaluation Fuzzy customer segmentation with important indicators (Section 5.1) Action planning and implementation of customer strategies Analytical CRM (Chapter 4) Operational CRM Strategic CRM Figure 29: Structure of Chapter 4 and 5 - 45 - Fuzzy market segmentation (Section 5.2) ment, and Chapter 5, Fuzzy Customer Segmentation, are shown in Figure 29. Chapter 4: Analytical Customer Relationship Management 4.1.2 The Development to the Customer Oriented Company After the change from seller’s to buyer’s markets about 40 years ago, the quality orientation, Total Quality Management (TCM), became increasing important in companies. Hence, until the end of the 1980s, firms focused mainly on the improvement of manufacturing processes, on the product quality and the integration of in-house product data (see Figure 30). Thereafter, companies started to align the product quality to the customers needs and, within the scope of Business Process Re-Engineering (BPR), to redesign business processes. Due to information systems, such as Sales Force Automation (SFA) or Computer Aided Selling (CAS), business processes were customised and production or sales data integrated. Since the 1990s, many companies have to align the complete value chain and the organisation to customers, especially in high competitive markets. With the rise of Customer Relationship Management (CRM), many companies became more customer-oriented. Thereby, the sale of a product or service is not considered as a business transaction only, but as the beginning of a customer relationship. In addition, a consistent view of customers in enterprises often is only possible by integrating all customer relevant data in a CRM information system. Focus: customer satisfaction Focus: customer retention Integration of all customerrelated data Process orientation Integration of the production and sales data Integration of the in-house product data Business Process Re-Engineering (e.g. SFA/CAS) Customer orientation Customer Relationship Management (CRM) CRM Trends: increasing IT-applications systematisation individualisation differentiation profit orientation Quality orientation Total Quality Management (TQM) 1980 1990 2000 Source: adapted from [Sieben 2001, p. 298, Rapp 2005 p. 42] Figure 30: The Development to the Customer-Oriented Company Within the field of CRM, several trends can be observed: CRM became more and more systematic, individual, differentiated and, due to innovations in IT, highly technical in the last years. The profit orientation and the controlling of CRM and CRM processes also increased. The main ideas of customer (relationship) management are not new, but as old as people doing business. Concepts like customer satisfaction and retention, which have been discussed since the 1970s, are still the basic for long-term and profitable relationships. However, the importance and potential of CRM is highly increasing due to technological innovations and software in IT. - 46 - Chapter 4: Analytical Customer Relationship Management 4.1.3 CRM and Customer Management CRM is only one, but an important approach in the domain of customer management and marketing. Figure 31 illustrates the development of the different fields in customer management. Most of them are promising for business applications for fuzzy classification. According to [Belz and Bieger 2004, 2006], the weight and diffusions of the different approaches can vary strongly over different industries. Weight of different approaches in customer management Small customer management fc Partnership systems Customer acquisition fc Global account management Key account management fc One-to-one marketing fc Direct marketing fc Customer relationship management fc Customer retention fc Lifestyle segments Market segmentation fc fc Mass customisation fc Mass marketing 1970 Promising fc fields for fuzzy classification 1980 1990 Primary focus of the paper 2000 Secondary focus 2010 t Not specified Source: adapted from [Belz and Bieger 2004, p. 56] Figure 31: Applications of Fuzzy Classification in the Domain of Customer Management The primary focus of this thesis is the application of fuzzy classification in the domain of Customer Relationship Management (CRM), which includes customer segmentation, acquisitions and retention (compare Figure 31). Especially in saturated markets, which is the case in many industries, customer retention is increasingly important, but also difficult. Mass customisation and one-to-one marketing are particularly interesting for fuzzy classification as it facilitates to identify and segment customers according to their individual behaviour towards the company. - 47 - 2) Customized marketing fc 1) Individual marketing fc (Focus: product & customer) (Focus: product) fc Personalisation fc Product design fc Product configuration … fc Mikromarketing Self-customisation fc Customer profiling Learning relationship fc Mass customisation fc Database marketing fc One-to-one marketing 4) Mass/transactional marketing 3) Relationship marketing fc (Focus: sale) (Focus: customer) Partnership Standard products … Transaction Customer integration … Repurchases fc Possible marketing concepts for fuzzy classification fc Loyalty programs fc Retention programs fc Satisfaction controlling Intensity of customer relationship Individualisation of the product/service Chapter 4: Analytical Customer Relationship Management Source: adapted from [Muther 1998, p. 54], [Payne 2006, p. 8] Figure 32: Fuzzy Classification and Individual Marketing Fuzzy classification allows treating customers or customer segments more individually. Therefore, fuzzy classification is not only promising for customised marketing (for instance for the fuzzy classification of products, their design or configuration) and relationship marketing (e.g. to classify less loyal customers in order to launch loyalty programs), but also for individual marketing like mass customisation, customer profiling or for database marketing (in Figure 32). The idea of one-to-one marketing, which originally trace back to [Peppers and Rogers 1993, 1997], is to learn from the customer ("learning relationship") and to improve the relationship and knowledge about the customer and his needs by cooperation (for instance through customers’ feedback or observations) in order to treat customers individually. One-to-one (or individual) marketing and mass marketing differ in many topics. Table 13 contrasts these two concepts and shows the possible applications for fuzzy classification in one-to-one marketing. Table 13: Mass Marketing vs. One-to-One Marketing and Applications for Fuzzy Classification Mass Marketing Average customer All customers No segmentation Customer anonymity Standard product Mass production Mass distribution Mass advertising One-way message Mass promotion Economics of scale Share of market Customer attraction Short-term focus One-to-One Marketing Individual customer Profitable customers Customer segmentation Customer profile Customised marketing offering Customised production Individualised distribution Individualised message Two-way message Individualised incentives Economics of scope Share of customer Customer retention Long-term focus Applications for Fuzzy Classification fc Performance measurement of individual customers Fuzzy customer analysis and segmentation (microsegmentation), key account management Fuzzy classified customer profile Fuzzy classification based customisation, individualistion, configuration or personalisation of products/services Individualised campaigns and messages based on fuzzy segmentation of customers or (target) segments Fuzzy calculation of personal prices, offers or discounts Optimised share of customer/wallet by cross-/up-selling Retention programs for based on fuzzy retention portfolios Source: adapted from the scheme of [Kotler and Keller 2005, p. 155] - 48 - Chapter 4: Analytical Customer Relationship Management 4.1.4 Definition of CRM The term Customer Relationship Management (CRM) is defined differently. Put simply, CRM is “information-enabled relationship marketing” [Payne 2006, p. 11]. A rather technical definition considers CRM as “the automation of horizontally integrated business processes involving front office customer points (marketing, sales, service and support) via multiple, interconnected delivery channels [Peelen 2005, p. 3].” Other definitions describe CRM as a process that addresses all aspects of identifying customers, creating customer knowledge, building customer relationships, and shaping their perceptions of the organisation and its products. The Gartner Group describes CRM as „an IT enabled business strategy, the outcomes of which optimise profitability, revenue and customer satisfaction by organising around customer segments, fostering customer-satisfying behaviours and implementing customer-centric processes” [Payne 2006, p. 5]. Phase model Processes (tasks) Market research Subject area fc can be used for the identification, classification, analysis and development of promising markets or market segments (Chapter 5.2 Market Segmentation). fc Demand analysis fc Public relations Information Advertising fc Sales promotion fc Campaigns fc Marketing fc Customising fc Service Price calculation fc Financing fc Sales Contract conclusion fc Order processing Handling of payment fc Purchase Finance Delivery Startup Sales Installation Maintenance Repairs After sales Service Complaints Database marketing and fc support the configuration, customisation, individualisation or personalisation of products, services and communication. Thanks to fc, prices, estimates, accounts, paying conditions (e.g. warranties) and contracts can be calculated and offered more flexibly and personally in order to set incentives to improve buying attitudes, retain customers and to drive customer equity & profit. With fc important customer information, indicators or values of finance and accounting (e.g. customer turnover, contribution margins, profits, equity, customer lifetime value) can be better analysed and evaluated in order to manage customer relations effectively. With fc, services and customer care can be aligned more personally, customer- and segment-oriented (e.g. additional services for strategic key customers). By fuzzy classifying customers or customer segments, customer care can be realised more precisely and focused (e.g. on key, periled, unsatisfied customers). Customer service fc Customer care fc enables to realise individual campaigns e.g. for important, valuable customers (key account management) and for new or imperilled customers. Through adequate fuzzy customer segmentation, customers (or segments) can be informed specifically (depending on their needs or their purchase history). Tender preparation fc Offer fc can help to classify and analyse needs and demands of customers as well as to develop and provide corresponding products and services. fc allows advertising and promoting more effectively and efficiently by addressing the target customers or segments with adequate communication instruments. Individual campaign fc Information Use of fuzzy classification (fc) fc fc facilitates to bind customers with individual loyalty programs or incentives, like fuzzy personal accounts. Customer retention fc Source: adapted from [Schumacher and Meyer 2004, p. 39] Figure 33: The Use of Fuzzy Classification in Typical Tasks of CRM - 49 - Chapter 4: Analytical Customer Relationship Management Figure 33 shows typical tasks and processes in CRM, mostly promising for fuzzy classification. In CRM, a distinction is often made between strategic, analytical and operational CRM (see for instance [Meier 2003b, Hippner and Wilde 2004a, 2006, Peelen 2006]). Therefore, CRM application architectures (in Figure 34) often contain a strategic, analytical and an operational layer. Customers Brown Miller Personal contact Phone Mail WWW E-Mail Mobile technologies Customer Relationship Communications (CRC) Service Sales Management Information System (MIS) After sales Analytical CRM (aCRM) Customer Relationship Operations (CRO) Strategic CRM Mass media Data mining & OLAP Fuzzy queries & gathering of data fCQL toolkit Enterprise Ressource Planning (ERP) Supply Chain Management (SCM) CRM software Computer Integrated Manufactering (CIM) fc Closed loop DWH architecture Relational Database Management System Customer Relationship Analytics (CRA) fc fc External data CRM service systems fc Customer Performance Measurement (CPM) Operational CRM Front office Ford Customer contact points Marketing Back office Strategic and operational objectives Smith Process-based strategic planning Fuzzy customer segmentation and targeting Customer acquisition strategies and programs Customer loyalty/retention or recovery strategies and programs Add-on selling (cross-/down-/up-selling) strategies Source: adapted from [Hippner et al. 2001b, p. 201, Meier 2003b, p.10, Neckel and Knobloch 2005 p. 45] Figure 34: CRM Application Architecture At the strategic layer at the bottom, strategies and operational objectives for customer acquisition, retention and recovery are defined as well as add-on selling strategies. The operational layer at the top, with the components Customer Relationship Communications (CRC) and Customer Relationship Operations (CRO), is in touch with the customers. Customers communicate und interact with the company through different channels or media. The analytical layer in the middle, analytical Customer Relationship Management (aCRM), includes an Information (IS) or a Management Information System (MIS), a Relational Database Management System (RDBMS), a customer Data Warehouse (DWH), CRM software, data mining tools or other CRM service systems, which contain customer data. The query process with fCQL deals with the RDBMS and DWH within the layer of aCRM, as shown in Figure 34. - 50 - Chapter 4: Analytical Customer Relationship Management Stationary networks Stationary user; sales or customer manager Analytical CRM RDBMS DWH Customer data (customer information) Mobile networks Internet Server Desktop WLAN LAN EDGE HSDPA UMTS (E)GPRS Mobile Analytical CRM Laptop Bluetooth Tablet PC PDA Smart phone Cell phone CRM eCRM Mobile CRM Customers Intranet fCQL & SQL queries Mobile user; sales or customer manager classify from with Operational CRM Figure 35: Mobile Analytical Customer Relationship Management To undertake fuzzy queries with fCQL, the desktop user (e.g. a sales or customer manager) can access the RDBMS or DWH over a conventional, stationary network (intranet; see Figure 35). In the case of mobile analytical CRM, a field manager has wireless connection to the customer data over mobile networks and the internet, using a laptop, PDA or a smart phone. With mobile technologies, a customer or sales manager has flexible access to relevant and actual customer information (anytime – anywhere). In addition, electronic and mobile CRM improve operational activities, for instance to prioritise customer care or services, and to improve time management. 4.1.5 Objectives and Key Points of CRM CRM is not an end in itself. Its main objectives are to increase customer profits and customer equity, which is defined here as the monetary value of a company’s current customers. In order to augment the profitability of customer relationships, a number of requirements have to be fulfilled: first of all, the company has to focus and align its processes towards its customers, in order to identify, recognise and analyse the needs and wants of the target customers, or of a segment, regarding the company and its products or services. Second, the products or services offered should meet the customers’ expectations and create a visible value for them. Customer value is defined here as the value creation from a customer perspective, that means the entire product, services, personnel and image values that a buyer receives from a marketing offer (compare [Kotler et al. 2005, p. 464] and Subsection 5.1.6: Customer Value). Consequently, the term ‘customer value from the customer perspective’ is not to be confused with the term ‘customer value from the company perspective’ or Customer Lifetime Value (CLV). However, customer value contributes significantly to customer satisfaction, the fulfilment of the customer’s needs or expectations. Increasing satisfaction and commitment raises customer loyalty and customer retention [Reichheld and Sasser 1990, Boulding et al. 1993, Anderson and Sullivan 1993, Rapp 1995, Oliver 1996, Bolton 1998, Mital and Kamakura 2001, Homburg 2006, Krafft 2007, Bruhn 2007, Bruhn and Homburg 2005, 2006, Homburg and Krohmer 2006]. - 51 - Chapter 4: Analytical Customer Relationship Management Empirical research show significant positive correlations of satisfaction (or loyalty) and operating margins like sales, turnover and cash flows [Bolton 1998, Rust et al. 1995], Return on Investment (ROI, e.g. [Anderson et al. 1997], for a review see [Zeithaml 2000]), Return on Customer Investment (ROCI; for instance [Hayman and Schultz 1999]), Return on Relationship (ROR; see for example [Gummesson 1999]), accounting returns [Ittner and Larcker 1998] firm value and a firm’s raw market value [Ittner and Larcker 1996] and shareholder value and stock prices [Anderson et al. 2004, Fornell et al. 2006]. Increasing customer satisfaction and thereby higher retention secures future revenues [Fornell 1992, Rust et al. 1995, 2005] and reduces costs of future customer transactions, such as ones associated with sales, transport, service and payment (see for instance [Reichheld 1993, 1996, Reichheld and Sasser 1996, Srivasatava et al. 1998]). Consequently, sales, turnover and net cash flows are higher. At the same time, greater customer retention indicates a more stable customer base that provides a relatively predictable source of futures revenue due to repurchases and add-on sellings In addition, recommendations of satisfied customers lead to lower acquisition costs and to additional revenues from new customers. As a result, the long-term profits of the firm increase, their volatility tends to be lower, and the risk associated with the anticipated cash flows is reduced. Therefore, market value and shareholder value increase (see [Anderson et al. 2004, p. 173]). All the discussed empirical findings of research on CRM can be summarised in a CRM success chain (compare Figure 36). Customer investments Customer orientation n Customer attitude Customer value o Customer satisfaction Customer needs Customer expectations Behavioural intentions Customer loyalty p Customer behaviour Customer equity,CLV Customer retention Recommendations word of mouth q Customer results Market value Network effects Market share r Shareholder Cu. Profit, Contr. margins Repurchases Perceived value & price/performance Commitment & attachment Cross-/up-selling Turnover, sales, cash flow Share of wallet Image Quality of relationship Perceived product or service quality Switching Enthusiasm costs factors Price sensitivity Marketing management Customer costs (sales, marketing,…) Accounting & finance Firm & shareholder value management Product and service management Customer Performance Measurement (CPM) & Customer Relationship Management (CRM) Performance measurement and management Figure 36: CRM Success Chain - 52 - Chapter 4: Analytical Customer Relationship Management Each indicator of the success chain can be assigned to a psychological construct of a simple model: products and services (n; customer investments) influence customer attitudes (o), such as the perceived customer value and the perceived product, service or relationship quality, which effect customer satisfaction. Customer attitudes towards the company and its products and services lead to behavioural intentions (p), for instance, the intentions to repurchase the same or other products from the company. Customer behaviour (q) is whether they really repurchase (or not), cross-buy or recommend products to friends, for instance. Their behaviour leads to customer results (r), e.g. customer turnover, contribution margins and profits. It is a strategic task for firms to analyse, control and manage the different customer indicators proposed in the CRM success chain. This is a challenge for both marketing management, on the left side of Figure 36, and for managerial accounting or finance on the right. Such performance measurement and management should not only consider organisational, production- or process-related and financial indicators, measures, numbers, metrics or figures, but, in particular, market- and customer-related performance indicators. The "small CRM success chain" in Figure 36, or similar success chains, discussed for instance in [Bruhn 2007], contain important constructs of marketing (for instance customer satisfaction, loyalty, retention). However, this small CRM success chain does not provide enough customer information and customer performance indicators for a customer performance measurement system, since the aggregation level of information is too high. Consequently, more indicators have to be defined and taken into account. That means that the "small CRM success chain" has to be enlarged to a "big CRM success chain" with a comprehensive number of different indicators. “Only what get’s measured is managed and done.” According to this management slogan, CRM and marketing cannot manage its clients, if customers cannot be described, measured and evaluated. Typically, these processes are based on customer data and information. Consequently, CRM requires a number of relevant customer criteria and customer performance indicators, as discussed in the following section. - 53 - Chapter 4: Analytical Customer Relationship Management 4.2 Customer Performance Measurement 4.2.1 Definitions Entering rather new territory of research, this section develops a new concept of customer performance measurement and management by considering a comprehensive number of different, but relevant customer performance indicators. First of all, since there are no common definitions of several basic expressions for this purpose, the different terms have to be derived from related expressions and are defined as follows. Performance is, among others, the observable or measurable behaviour of a person [Oxford 1989]. Derived there from, customer performance can be defined: Customer Performance (CP) is a measurable monetary or non-monetary result of a customer relationship in a defined period. To operationalise ‘performance’, performance measurement is used. However, performance measurement is a topic which is often discussed but rarely defined [Neely et al. 1995]. Performance Measurement (PM), for the purpose of this work, is understood as the measurement, analysis and communication of performance [Wettstein 2002, p. 19]. Applied on customer performance, customer performance measurement can be defined as follows: Customer Performance Measurement (CPM) is the acquisition, analysis and the evaluation of performance-related customer information. However, CPM has many facets and can be characterised by following dimensions of customer performance measurement: the unit, format, planning, interval, time, alignment, connection with incentives, CRM layer and the aggregation level. The values of these dimensions can be very different, as shown in Figure 37. 1) Unit 2) Format discrete membercustomer qualitative ship functions loyalty non-monetary continuous functions customer quantitative monetary turnover 8) Aggregation level high all customers, customer segment customer strategies 7) CRM layer one customer operational strategic variation long-term low – high 1– 100 short-term Customer Performance Measurement (CPM) low sale 3) Planning interval ∆X↓ improvement X↑ 6) Connection with incentives 5 years 1 month ex post ex ante lagging-indicator leading-indicator internal 4) Time CRM, employee external customer 5) Alignment Source: adapted from [Müller-Stewens 1998, p. 37, Gleich 2001, p. 11, Reinecke 2004, p. 48] Figure 37: Dimensions of Customer Performance Measurement - 54 - Chapter 4: Analytical Customer Relationship Management Performance management is “a philosophy which is supported by performance measurement” [Lebas 1995, p. 44]. That means that performance measurement is a part of performance management. However, performance management is understood as a management function (analysis, planning, implementation and control) and encompasses the methodologies, metrics, processes, software tools and systems that manage the performance [Cokins 2004]. Consequently, customer performance management is defined here as a CRM function and encompasses all customer performance indicators, instruments, processes, software tools and systems of CRM to analyse and control customer performance. Finally, a Performance Measurement System (PMS) is defined as “a set of metrics used to quantify both, the effectiveness and the efficiency of actions” [Neely et al. 1995, p. 5]. However, a Customer Performance Measurement System (CPMS), as an instrument of analytical CRM, is defined here as an information or CRM system used to analyse, evaluate, control and communicate customer performance and customer strategies. 4.2.2 Processes of Customer Performance Measurement Following the discussed CRM success chain, each company should select and define an adequate number of important customer performance indicators (o in Figure 38; the term customer performance indicator is defined and discussed in the next subsection). n Requirements for indicators o Selection of customer performance indicators Z Collection of customer data [ Fuzzy classification r Analysis of results s Evaluation & segmentation t Action planning Figure 38: Processes of Customer Performance Measurement However, the chosen indicators have to meet several requirements (n) of performance measurement theory and practice (see for instance [Bruhn 2003a, p. 89, Reinecke 2004, p. 329, Vollmuth 2006, p. 23, Probst 2006, p. 18]). Customer Performance Indicators (CPIs) in particular have to be customer-specific (causality and traceability of CPIs to a customer) relevant (high importance of CPIs for customer relationship management and marketing) well-defined (precise definition and description of CPIs) available (availability and accessibility of CPIs in an IS, MIS or within a company) measurable (measurability of CPIs with continuous or discrete membership functions) objective (intersubjective traceability of CPIs) - 55 - Chapter 4: Analytical Customer Relationship Management comprehensible (plausibility and understandability of CPIs) up-to-date (up-to-dateness of CPIs) user-friendly (user-friendliness of CPIs) accepted (acceptance of CPIs by employees and managers of CRM or by management) comparable (comparability of CPIs over time or with competitors) economical (proportion of the costs of data collection to benefit of CPIs) decision-/target-oriented (importance of CPIs for action planning and decision making) reliable (high reliability of CPIs and low random error) and sensitive (CPIs should be suited for an early warning system or a trigger mechanism). However, after the selection of customer performance indicators, employees or managers of CRM, marketing and IT have to collect, record, store and administrate customer data (Z in Figure 38) in a Customer Performance Measurement System (CPMS) or in an information system. Since information management mostly has to classify customer data, for instance as ‘low’, ‘medium’ or ‘high’ performance of indicator X, one- or multidimensional fuzzy classification ([) is a crucial step in the processes of customer performance measurement. This thesis suggests to classify all customer performance indicators fuzzily in order to avoid misclassifications and to improve the quality of customer evaluations and CRM. Fuzzy classification of customer data is a precondition to analyse (\), evaluate and to fuzzily segment customers (]). Based on different fuzzy classified and company-relevant customer performance indicators, customers can be analysed, segmented by CRM or marketing. As a result, customer specific CRM or marketing strategies and actions can be planned, communicated and realised (^) in order to improve customer performance on an individual and on a corporate level. - 56 - Chapter 4: Analytical Customer Relationship Management 4.3 Customer Performance Indicators 4.3.1 Definitions To simplify and aggregate customer data, different indicators and measures are used for performance measurement. Consequently, customer performance measurement has to rely on an adequate number of customer performance indicators. A Customer Performance Indicator (CPI) is defined here as a customer-related monetary or non-monetary criterion (a measure, metric, index, figure or ratio) about customer performance. In this thesis, Customer Performance Indicators (CPIs) are categorised under six categories: 1) Customer Performance Indicators for Revenue and Profitability (CPIP) 2) Customer Investment Indicators (CII) 3) Customer Relationship Indicators (CRI) 4) Customer Recommendation Indicators (CReI) 5) Customer Information Indicators (CInfI) and 6) Customer Cooperation Indicators (CCI). Appendix 4 (pp. 136ff) shows a collection of 170+ Customer Performance Indicators (CPIs), with the definition, operationalisation, measuring units and the purpose of each indicator. In addition, each indicator can be either assigned to the construct ‘customer investment’, ‘customer attitude’, ‘customer behavioural intention’ ‘customer behaviour’ or ‘customer result’. Most indicators can be measured at an individual level (*) to analyse the performance of a single customer, or as an aggregate indicator (∑*) to evaluate the performance of all customers or of a segment. Depending on the company, the size of the enterprise, market or on the industry, some indicators are more important, other less. However, the important indicators are called: Key Customer Performance Indicators (KCPI; symbol: ) are defined here as important monetary or non-monetary customer performance indicators reflecting critical success factors for customer relationships. In contrast, leverages (symbol: ) are influenceable or controllable variables to manage successfully CRM processes in order to improve customer performance. Customer (key) performance indicators, have different functions. They are used for the comparison of the target and the actual customer performance operationalisation of objectives and the ‘management by objectives’ of marketing and CRM prioritisation and realisation of objectives and decisions referring to the customers and CRM justification of decisions or actions (indicators, data and facts instead of acts on instinct) communication and management of customer-related tasks and processes controlling and monitoring of customer and market performance and for action planning. - 57 - Chapter 4: Analytical Customer Relationship Management 4.3.2 Categories of Customer Performance Indicators As mentioned, the CPIs are categorised under six different categories: 1. Customer Performance Indicators for Revenue and Profitability (CPIP) contain criteria, which are dependent on the customer’s past, actual or future performance regarding his purchases, e.g. purchased products (I 20 in Appendix 4), number, intensity, frequency of orders (I 17, I 26, I 28), volume (I 21) or value (I 23, I 29) of purchases and repurchases (I 56), turnover or sales (I 31), share of wallet (I 39), cross- and up-selling (I 50 - I 53), payment history (I 66), e.g. punctuality of payment (I 63) and creditworthiness (I 68), and profitability (I 78), e.g. customer contribution margins I to IV (I 69 - I 73), gross or net profit (I 75, I 76) and growth of profit (I 77), customer equity (I 79) and Customer Lifetime Value (CLV; I 80). As shown in Figure 39, CPIPs, for instance customer profit, often are operational, monetary, quantitative, lagging and internal indicators to improve. However, each CPIP has different characteristics, depending on the task and context of customer performance measurement. 1) Unit 2) Format non-monetary qualitative monetary 8) Aggregation level high operational 7) CRM layer quantitative long-term short-term Example of CPIP: customer profit (I 76) low strategic 3) Planning interval variation ex post ex ante 4) Time internal improvement external 6) Connection with incentives 5) Alignment Figure 39: Measurement Dimensions of the CPIP ‘Customer Profit’ 2. Customer Investment Indicators (CII) consider all customer costs or investments incurred in a customer relationship in a defined period. Some examples: customer acquisition, retention and recovery costs (I 87-I 92), customer efficiency (I 108) transaction (I 94), sales (I 95), service (I 97), communication (I 99), contact costs (I 100) marketing costs per customer (I 101) or total customer costs (I 102) "return-on-"ratios like Return on Sales (ROS; I 103), Return on Customer (ROC; I 104), Return on Relationship (ROR; I 105), Return on Customer Satisfaction (I 106), Return on Retention (I 107), Return on Marketing (ROM; I 109) or Return on Investment (ROI; I 110). 3. Customer Relationship Indicators (CRI) are mainly qualitative, non-monetary, long-term, external and strategic indicators about a customer relationship (see Figure 40), such as - 58 - Chapter 4: Analytical Customer Relationship Management customer perceived product (I 118, I 119), service (I 120) or relationship (I 149) quality, perceived price-performance ratio (I 121, I 122) and customer value (I 123, I 124) customer satisfaction in general (I 125 - I 127), with a product (I 128) or service (I 129) and customer commitment (I 131), attachment (I 132), loyalty (I 134) or retention (I 137 - I 142). 1) Unit 2) Format non-monetary qualitative monetary 8) Aggregation level high quantitative long-term short-term Example of CRI: customer loyalty (I 134) low operational strategic 7) CRM layer 3) Planning interval ex post variation ex ante 4) Time internal improvement external 5) Alignment 6) Connection with incentives Figure 40: Measurement Dimensions of the CRI ‘Customer Loyalty’ 4. Customer Recommendation Indicators (CReI) assess, for instance, the number (I 152) and intensity (I 153) of customer recommendations (Figure 41) or positive word of mouth. 1) Unit 2) Format qualitative non-monetary monetary 8) Aggregation level high low 7) CRM layer quantitative long-term short-term Example of CReI: number of recommendations (I 152) operational strategic 3) Planning interval variation improvement 6) Connection with incentives ex post ex ante 4) Time internal external 5) Alignment Figure 41: Measurement Dimensions of the CReI ‘Number of Customer Recommendations’ 5. Customer Information Indicators (CInfI) evaluate e.g. customer contacts (I 159), responses (I 169), number/quality of suggestions (I 163), complaints (I 164) or his product expertise (I 168). 6. Customer Cooperation Indicators (CCI) inform about a customer’s intention to cooperate (I 171) or his expertise for cooperation (I 172) or other indicators for cooperation. Figure 42 shows the coherence and relations of the 170+ Customer Performance Indicators (CPIs) in a "big CRM success chain". However, the cause-and-effects of the big success chain are ideal, theoretical causalities to illustrate the context and purpose of the different indicators. - 59 - Chapter 4: Analytical Customer Relationship Management Customer value (I 124) Customer satisfaction (IFigure 126-129) 42: Customer Customer acquisition (I 6) Enthusiasm factors Customer needs Value drivers (Fulfilment of) customer expectations (I 125) Corporate Image (I 115) Brand Image (I 116) Price-performance-ratio (I 122) Recommendations, word of mouth (I 151f) Commitment (I 131) and attachment (I 132) Perceived value or utility (I 123) Perceived product quality (I 118,119) Perceived service quality (I 120) Perceived relationship quality (I 149) Intensity of relationship (I 148) Intention/intention to switch (I 140,141) Switching costs (I 145; e.g. functional/contractual I 146) Trust Involvement (I 133) (I 130) Awareness Number of new customers (I 4) Number of customers (I 7-9) # of migrated customers (I 10) Share of wallet (I 39-41) Customer penetration (I 38) Price sensitivity Ad awareness (I 112) Payment history Intention to dialog, response rate (I157,169) Number/quality of suggestions (I 163) Product knowledge/ expertise (I 113,168) Expertise for cooperation (I 172) Consulting/helpdesk intensity (I 158) Number/quality of complaints (I 164) Demand of technical service (I 166) Possible cooperation topics (I 173) Customer initiated contacts (I 159,162) Complaint satisfaction (I 165) Number of returns (I 167) (I 60,61) (I 63-68) Cross- & upselling (I 50-54) Repurchase intentions (I 55) Market value Growth (sales I 35, Market share (I 43,44) Retention costs/efficiency (I 89,90) Customer efficiency (I 108) Return on relationship (I 105) Transaction costs (I 94) Service costs (I 97) (After) sales costs (I 95,98) Market penetration (I 48,49) Return on investment (I 110) Return on marketing (I 109) Return on customer (I 104) Return on sales Customer profit (I 75-78) Contribution margins (I 69-74) Distribution & logistic (I 95) Communication costs (I 98) Firm value profit, m.share I 45) (I 87,88) Recovery costs/efficiency Shareholder value Total customer costs (I 102) Marketing costs (I 101) Contact costs (I 100) (I 103) Customer turnover/sale (I 31-35) Cash flows (I 30) Customer Investment Indicators (I 87-110) Purchased products (I 20) Purchased volume (I 21) # of orders Order value (I 56,57) (I 17) (I 23) Heavy usage index (I 22) Purchase intensity (I 26) Recency Frequency (I 27) (I 25,28) Monetary value (I 29) Repurchases Customer Information Indicators (I 157-170) Acquisition costs/efficiency (I 91,92) # of recovered customers (I 11) (I 111,114) Intention to cooperate (I 171) Customer Cooperation Indicators (I 171-173) Customer equity (I 79) and Customer retention (I 137-139; 142-144,147) Performance 134) loyalty (I Chain CustomerIndicators Lifetime Value (I 80) CRM Success with 170+ Customer Key Customer Performance Indicator (KCPI) Leverage Customer Relationship Indicators (I 111-150) Customer Performance Indicators for Revenue and Profitability (I 1-86) Figure 42: CRM Success Chain with 170+ Customer Performance Indicators (For Definitions and Details on Indicators see Appendix 4, pp. 136ff) - 60 - Purchase Data Customer orientation (I 117) Chapter 4: Analytical Customer Relationship Management 4.3.3 Customer Performance Indicators in Business Practice Business practice focuses mainly on financial performance indicators, ratios, numbers and figures like sales (1. in Figure 43), cash flows, contributions margins (3.), profits (4.) or market share (2.; see [Ambler 2000, Rudolf-Sipötz 2001, Reinecke 2004, Barwise and Farley 2004, Farris et al. 2006, Krafft 2007]). Consequently, most companies evaluate financial, easily measurable customer performance indicators, such as turnover (27./34.) or contribution margins (26./35.). Qualitative criteria like customer satisfaction (5./33.), loyalty or retention (14.) or the perceived service and product quality (17./18.) are also often measured indicators in daily business. In addition, CRM practice collects customer data like the number of new customers (23.) or complaints (32.) or the customers’ payment history (25./36.). Marketing & sales performance indicators 1. Sales (turnover and/or volume; I 21,31-35) 2. Market share (I 43) 3. Gross margins or gross contributions (I 69-74) 4. Net profit (I 76) 5. Customer satisfaction (I 125-129) 6. Return on sales (I 103) 7. Sales growth relative to market growth (I 45) 8. Relative market share (I 44) 9. Sales per employee 10. Relative price (compared with main competitor) 11. % of new customers relative to portfolio (I 5) 12. Proportion of sales generated by new products 13. Distribution level 14. Customer loyalty or retention (I 134-147) 15. Proportion of own customers to potential total 16. Awareness (I 111-113) 17. Perceived service quality (I 120) 18. Perceived product quality (I 118,119) 19. Brand equity (brand strength) 20. Customer equity or lifetime value (I 79,80) 21. Capital turnover 22. Commitment (I 131; purchase intention, I 55) Indicators for customer acquisition 23. Number of new customers (I 4) 24. Potential of new customers (I 84) 25. Payment history of new customers (I 67) 26. Contribution margin of new customers (I 74) 27. Share of new customer’s sales to total (I 31) 28. Poached customers from competitors (I 3) 29. Number of prospective customers (I 1) 30. Sales or turnover of first-time buyers (I 32) 31. Acquisition costs (I 87) [Reinecke 2004] [Rudolf-Sipötz 2001] 78% 79% 81% 76% 91.5% 83% 68% 50% 63% 53% 53% 52% 50% 70% 63% 81% 36% 43% 57% 73% 66% 64% 38% 20% 65% 25% 36% 78% 41% 64% 77% 40% 55% 20% 40% 17% 32% 15% [Ambler 2000] 46% [Barwise and Farley 2004] 43% 54% 36% 66% 39% 20% 37% 77% 22% 18% Empirical studies Indicators for customer retention 32. Number of complaints (I 164) 33. Customer satisfaction (I 125-129) 34. Customer turnover or sales (I 31,33-35) 35. Contribution margins (I 69-73) 36. Payment history (I 63-66,68) 37. Share of wallet (I 39,41) 38. Frequency (I 28) 39. Duration of relationship (I 147) 40. Churn rate (I 144) 41. Product portfolio of customers (I 58,59) 42. Retention costs (I 89) 91% 96% 65% [Reinecke 2004]: n = 419/276 Percentage of usage 64% 55% 54% 44% 62% 63% 24% 28% 27% 36% 35% 12% 85% 81% 59% 52% [Rudolf-Sipötz 2001]: n = 155 Percentage of usage [Ambler 2000]: n = 200 Percentage of usage [Barwise and Farley 2004]: n = 697 Percentage of usage Source: [Ambler 2000, p. 8], [Rudolf-Sipötz 2001, p. 74], [Reinecke 2004, p. 153, 274, 294], [Barwise and Farley 2004, p. 259] Figure 43: Empirical Results of Customer Performance Measurement in Companies - 61 - Chapter 5 Fuzzy Customer Segmentation - 62 - Chapter 5: Fuzzy Customer Segmentation 5.1 Fuzzy Customer Segmentation with Important Indicators 5.1.1 Definitions Each company has different kinds of customers. Customers have different needs, different expectations about products or services, different buying or using behaviour of purchased products and different information or communication behaviour. In addition, from a company point of view, customers perform differently. In the words of [Peppers and Rogers 1997, p. 31]: “Customers have different needs from a firm, and they represent different valuations to a firm.” Consequently, it makes sense to divide customers into groups with similar characteristics or performance. This process of dividing different customers into homogeneous groups, is called customer segmentation. Based on customer segmentation, the company can adapt the marketing mix to the different customer segments, e.g. by mass customised products or by segment specific communication. Customer-oriented definitions of customer segmentation are often used in literature. [Bruhn 2003a, p. 88] states: “Customer segmentation refers to a classification of all potential and current customers, based on their market reaction, into inherently homogeneous but externally heterogeneous sub-groups (i.e. customer segments)”. However, a company could follow another approach by asking: who are our most interesting, valuable, profitable or promising customers? This company-oriented interpretation of customer segmentation has another context and other objectives: the identification and separation of the most valuable customers for the company. Customer criteria, which can be influenced by the company, are called endogenous criteria. The following endogenous groups of segmentation criteria can be applied for customer segmentation [Bruhn 2003a, p. 90]: Economic endogenous criteria, for example customer sales or turnover (I 31), contribution margins (I 69-I 74), profits (I 75-I 78), customer equity (I 79) or customer lifetime value (I 80,I 81) Behavioural endogenous criteria, like customer retention (I 137), recommendations (I 152), add-on-selling (I 50-I 53), repurchases (I 56), punctuality of payment or creditworthiness (I 68) Psychological endogenous criteria, for instance the perceived service, product, or relationship quality (I 118-I 120; I 149), customer value (I 124), satisfaction (I 126) or loyalty (I 134). Based on these endogenous criteria, for example ‘valuable’ and ‘not valuable’, ‘promising’ and ‘non-promising’, or ‘satisfied’ and ‘dissatisfied’ customers can be separated from each other. Since a customer should not be labelled sharply only ‘valuable’ or ‘not valuable’, customer segmentation and evaluation should be done fuzzily. Fuzzy customer segmentation is defined here as the fuzzy classification of the company’s current customers into similar, fuzzy segments, using different customer performance indicators (i.e. economic, behavioural and/or psychological endogenous segmentation criteria). - 63 - Chapter 5: Fuzzy Customer Segmentation 5.1.2 Fuzzy Clustering As defined in Section 2.1, any class or a combination of classes of a one-, two- or multidimensional fuzzy classification can be defined as a fuzzy segment. However, it was assumed that the classes where the data is classified in are known and fix. In reality, data usually do not fit in given classes. Since the classes should be adapted to the data and not the other way round, the classes have to be identified first. This identification can be done by cluster analysis. Cluster analysis is a multivariate data analysis method to reduce complexity of a dataset by grouping elements or objectives to groups, i.e. to clusters. In contrast to classification, cluster analysis or clustering does not rely on predefined classes. [Han and Kamber 2006, p. 383] define: “The process of grouping a set of physical or abstract objects into classes of similar objects is called clustering”. To derive fuzzy classes from the data, non-disjunctive, fuzzy cluster algorithms can be used, as shown in Figure 44. Methods of cluster analysis Disjunctive (sharp) methods Hierarchical methods Partitional methods Divisive Agglomorative Non-disjunctive methods Overlapping methods Fuzzy-c-means Mixture models Gustafson-Kessel Gath-Gewa Fuzzy methods FMLE-method Figure 44: Fuzzy Methods of Cluster Analysis Considering non-disjunctive methods of cluster analysis based on fuzzy logic, different algorithms are discussed in data mining literature. [Höppner et al. 1999], for instance, examine the fuzzy-c-means-, Gustafson-Kessel-, Gate-Geva-algorithm and fuzzy-shell-clustering-methods. The most famous fuzzy algorithm, the fuzzy-C-Means-algorithm (FCM) is an advancement of the hard c-means. In contrast to the hard c-means, where objects are assigned clearly to clusters, the FCM defines membership degrees between 0 and 1 for each object to the clusters. The FCM assumes that all clusters have approximately the same shape and size. The Gustafson-Kessel-algorithm, in contrast, takes the structures of the data into account. The Gate-Geva-algorithm is an extension of the Gustafson-Kessel-algorithm and considers additionally the size and density of the clusters. The less important fuzzy-shell-clusteringmethods describe mathematically the shape and distance of data to the geometric structure. Finally, the Fuzzy-Maximum-Likelihood-Estimation-algorithm (FMLE-algorithm) is based on a probabilistic evaluation (see for instance [Timm 2002]). - 64 - Chapter 5: Fuzzy Customer Segmentation a) Sharp Customer Segments (Ssi) b) Fuzzy Customer Segments (Sfi) Indicator 2 Ss1 Ss2 Miller 100% Ss1 Brown 100% Ss1 Ss5 Ford 100% Ss2 Ss4 1 Indicator 1 Smith 100% Ss2 Sf3 Sf1 Sf2 00 1 Brown 53% Sf1 47% Sf2 Smith 48% Ss1 52% Sf2 Ford 48% Sf2 Sf5 28% Sf4 24% Sf5 μ low indicator 1 Miller 100% Sf1 Sf4 Indicator 1 Ss3 μ low indicator 2 μ high indicator 2 Indicator 2 μ high indicator 1 Figure 45: Sharp (a) and Fuzzy (b) Customer Segments In Figure 45a, for example, five sharp segment are defined (Ss1 to Ss5) by a sharp cluster algorithm. Ford and Smith both belong entirely to segment 2 (Ss2), Brown and Miller to segment 1 (Ss1). Such a sharp segmentation can be problematic, as the examples of Smith and Brown show: although they have nearly the same values of the indicator 1 and 2, they are classified in two different segments. If segment 2 (Ss2) would be defined a little bit larger (dashed circle in Figure 45a), Brown would belong to the same segment 2 as Smith. If segment 1 (Ss1) would be enlarged (dotted circle), both Smith and Brown belong to segment 1. Using a fuzzy clustering algorithm, for instance the fuzzy-C-Means-, Gustafson-Kessel, GateGeva- or the Fuzzy-Maximum-Likelihood-Estimation-algorithm, the borders between the different segments become fluent (Figure 45b). That means that the sharp borders between the segments disappear. Fuzzy classified elements can belong to several segments at the same time: Ford belongs to three segments (48% to Sf2, 28% to Sf4 and 24% Sf5); Smith and Brown belong both nearly half to segment 1 and 2. With fuzzy customer segmentation and the definition of fuzzy segments, customers’ positions can be shown more exactly. The probability of misclassifications is reduced and customers segments can be managed more flexible. Since the logic of fuzzy segmentation does not depend on the exact form of the segments or the segmentation, and to simplify matters, a normal fuzzy classification with four classes (as defined in Section 2.1) will be used for fuzzy customer segmentation in the following sections. 5.1.3 Methods of Customer Segmentation In literature on marketing, different approaches and methods of customer segmentation and evaluation are discussed (for a review see [Meffert 2000, Rudolf-Sipötz 2001, Reichold 2006, Günter and Helm 2006, Homburg and Krohmer 2006, Bauer et al. 2006, Krafft 2007]). - 65 - Chapter 5: Fuzzy Customer Segmentation Methods of customer evaluation and segmentation Monetary Turnover Contribution margins Profits Equity, CLV Non-monetary Customer value Satisfaction Loyalty (ladder) Duration of CR Retention, etc. fc (Fuzzy) ABC analysis One-dimensional Multidimensional fc (Fuzzy) scoring methods fc (Fuzzy) portfolio analysis fc Fuzzy classification static dynamic Application Customer performance indicators Figure 46: Methods of Customer Segmentation In Figure 46, a distinction is made between one-dimensional customer evaluation or segmentation methods (for instance the ABC analysis or the present value method of finance), and multidimensional methods (for example scoring methods and portfolio analyses discussed in Chapter 3, or other mathematical models). One-dimensional methods consider, on the one hand, monetary measures, such as customer turnover, contribution margins, profit or Customer Lifetime Value (CLV), and, on the other hand, non-monetary indicators like customer value, satisfaction, loyalty or retention. Fuzzy classification can be categorised as a multidimensional approach of customer evaluation and segmentation, which can be applied to other methods, as fuzzy portfolio analysis, fuzzy scoring model or as fuzzy ABC analysis (discussed in Chapter 3). In addition, both monetary and non-monetary customer performance indicators can be classified fuzzily. In order to evaluate customers comprehensively and to manage them successfully, different customer data have to be collected and integrated in a corporate information system. Customer data often are displayed in an information dashboard, accessible for the responsible customer managers and employees of CRM, marketing or of the executive board. The information dashboard of relevant customer data in Figure 47 shows a categorisation of following five categories of customer data: 1) Profile data contain conventional customer data like address data, i.e. the customer’s identification number, name, mail and e-mail address, phone numbers, or demographic data as customer’s age, gender, civil and family status, education, profession, etc. In addition, profile data may include psychographic data as a customer’s hobbies, interests, lifestyle and his buying or payment behaviour. 2) Purchase data inform about a customer’s purchase history, i.e. all purchase dates, his number, volume or value of purchased products or services, his purchase recency and frequency or the duration of the customer relationship. - 66 - Chapter 5: Fuzzy Customer Segmentation fc 1) Profile data Adress data #, Name, address, e-mail, phone, etc. Profile data Demographic data (age, civil & family status, education) Psychographic data (interests, lifestyle) Buying and payment behavior 2) Purchase data Dates of purchase Purchased products Purchased volume Heavy usage index Frequency Recency Monetary Ø order value Duration of RS 4) Service data 3) Customer Performance Indicators (CPIs) Customer relationship indicators 0.4 0.5 0.3 0.6 0.2 0.7 0.8 0.1 0.468 0.9 0 1 Customer orientation ¨Subsection 5.1.5 Perceived product/ service quality Customer value ¨Subsection 5.1.6 Customer satisfaction ¨Subsection 5.1.7 Customer attachment/commitment Customer loyalty ¨Subsection 5.1.8 Customer retention ¨Subsection 5.1.9 Customer Lifetime Cycle Performance indicators for profitability 0.4 0.5 0.3 0.6 0.2 0.7 0.8 0.1 0.739 0.9 0 1 RFM method Repurchases ¨Subsection 5.1.10 Add-on-selling ¨Subsection 5.1.11 Share of Wallet ¨Chapter 5.1.12 Price sensitivity Sales or turnover ¨Subsection 5.1.13 Contribution margins ¨Subsection 5.1.14 Customer profits ¨Subsection 5.1.15 Customer equity or Customer Lifetime Value (CLV) ¨Subsection 5.1.16 fc Inverse: promising performance indicators for fuzzy customer segmentation Customer investment indicators General 0.4 0.5 0.3 0.6 0.2 0.7 0.8 0.1 0.964 0 1 Acquisition costs Retention costs Recovery costs Administration costs Transaction costs Communication costs Service costs Contact costs (After) sales costs Total customer costs Marketing costs Return on’s: - sales (ROS) - customer satisfaction - customer (ROC) - relationship (ROR) - Marketing (ROM) - Investment (ROI) customer requests Demands of technical services Number and quality of complaints Number of returns 5) Contact data Date of contact Number, types, channel, intensity, costs of communication Frequency of actions Customer adviser Source: adapted from [Homburg and Sieben 2003, p. 427] Figure 47: Information Dashboard of Relevant Customer Data 3) Customer Performance Indicators (CPIs) hold a number of relevant performance indicators for the customer relationship, profitability and investment as discussed in the last Section 4.3. Following 12 Subsections 5.1.5 to 5.1.16 discuss some of these indicators shown in the middle of the ‘information dashboard of relevant customer data’ in Figure 47. 4) Service data contain information about the services a customer demanded, e.g. the numbers of general requests, support, the demand of technical services or the number and the quality of complaints or returns. 5) Contact data (action and reaction data) include all information about the number, dates, types, channels, intensity, frequency or costs of communication activities or of contacts with a customer. In Appendix 4, most service and contact data are categorised under customer information indicators. Some of the profile, purchase, service or contact data is generated directly at the points of customer contact, for instance in the front office (customer relationship communication and operations in the architecture of Figure 34). However, it is the challenge and principal task of analytical CRM to collect, integrate, store, analyse, administrate and to manage all existing customer data. Most of the customer data of the dashboard shown in Figure 47 can be used for the fuzzy customer segmentation process and for the definition of fuzzy customers segments: The customer manager may want to segment the customers according to their profile data, to their demographic or psychographic data (e.g. all young customers with similar lifestyles). - 67 - Chapter 5: Fuzzy Customer Segmentation Regarding the purchase data, all customers, for instance, with similar purchase frequencies or recency can be chosen and addressed for a marketing campaign. Another campaign may be launched in the segment of dissatisfied customers to know the reasons for dissatisfaction and to improve satisfaction. A specific retention program may be realised for the segment ‘key accounts’; for this, all customers with high turnover or profits are selected. Depending on the task, situation or strategy of CRM, different customer data, criteria or performance indicators can be used for ‘fuzzy customer classification’, for ‘fuzzy customer Customer strategies Fuzzy customer segments, CPIs Information demand Requirements Fuzzy customer segmentation Fuzzy Customer data; Customer Performance classified data, CPIs Indicators (CPIs) Customer performance measurement Counter measures CPIs and KPIs Fuzzy clusters and segments Evaluations & profiles Customer evaluation, scoring and profiling Fuzzy customer classification Fuzzy classified data, CPIs & fuzzy customer segments Early warning system Marketing Early warning system (trigger mechanism) and sales (trigger mechanism) Campaign management Fuzzy customer segments Evaluations, scores & profiles Retention programs Key account management Counter measures Analytical CRM Profile, purchase, service, contact data; CPIs CRM strategy development Operational CRM Customer Relationship Communication (CRC) and Operations (CRO) Strategic CRM segmentation’ and for ‘customer evaluation, scoring and profiling’ (see Figure 48). Figure 48: Context of Fuzzy Customer Segmentation Fuzzy classified customer data, CPIs and fuzzy segments allow to evaluate, qualify, score or profile customers more exactly and fairly. This enables, for instance, an improved Key Account Management (KAM), i.e. the management of a company’s most important customers and the formulation of customer or segment specific loyalty or retention programs. Campaign management is more effective and efficient by adapting communication, information or offers to the different needs and expectations of different fuzzy customer segments. In addition, an early warning system can warn the customer manager, if the performance of a customer, of a fuzzy customer segment or of the whole customer portfolio is rapidly decreasing in order to launch counter measures of strategic or operational CRM and marketing. - 68 - Chapter 5: Fuzzy Customer Segmentation 5.1.4 Selected Indicators for Fuzzy Customer Segmentation The way customers can be segmented fuzzily, will now be discussed with some examples of customer performance indicators of the ‘information dashboard of relevant customer data’ (Figure 47) and of the ‘small CRM success chain’. These indicators are chosen because they can be considered as important Key Customer Performance Indicators (KCPIs) or leverages. The following indicators in Figure 49 are discussed in the Subsections 5.1.5 to 5.1.16. Customer orientation Customer value Customer satisfaction (¨5.1.5) (¨5.1.6) (¨5.1.7) Customer loyalty (¨5.1.8) Perceived value/utility (¨5.1.9) (¨5.1.16) Network effects Repurchases (¨5.1.10) Commitment & attachment Perceived quality Image Customer equity,CLV Recommendations Customer needs Customer expectation Customer retention Quality of relationship Key Customer Performance Indicator (KCPI) Add-on selling (¨5.1.11) Switching Enthusiasm factors barriers Share of wallet (¨5.1.12) Price sensitivity Leverage Shareholder Market value Market share Profits (¨5.1.15) ROR, ROCI Contr. margins (¨5.1.14) Customer turnover, sales, cash flow (¨5.1.13) Customer costs Figure 49: Selected Indicators of the CRM Success Chain for Fuzzy Customer Segmentation By combining different customer performance indicators of the small (Figure 49) or big CRM success chain (Figure 42; Appendix 4), fuzzy customer portfolios analysis allow managers to identify and manage fuzzy customer segments. To drive the CRM success chain, a company has to maintain the good performance of all customers with high membership degrees to the promising classes CX-1 in Figure 50. In addition, strategic CRM has to define adequate strategies to improve the performance of customers classified in the less promising classes. C1-4) C1-3) C2-1) C2-4) C2-3) C6-2) C6-1) C6-4) C6-3) C5-2) C5-1) C5-4) C5-3) C3-2) C3-1) C3-4) C3-3) Repurchases or add-on selling Customer retention Customer equity or profit Customer equity Market share C2-2) Customer satisfaction C1-1) C4-2) C4-1) C4-4) C4-3) Customer retention C1-2) Customer loyalty or retention Customer value Customer satisfaction Customer orientation Customer value Figure 50: Driving the CRM Success Chain by Optimising Fuzzy Classified Portfolios - 69 - Chapter 5: Fuzzy Customer Segmentation 5.1.5 Customer Orientation Customer orientation Customer value Customer satisfaction Customer retention Customer loyalty Customer equity Market value Shareholder To succeed or simply to survive in today’s marketplace, a company has to be customer oriented or customer-centred [Kotler and Keller 2005]. Such a customer-driven company focuses on customer needs and wishes in designing its marketing strategies and on delivering superior value to customers. According to Kotler, only high customer orientation allows a customer-value-creating marketing, the second step of the success chain. Customer orientation (I 117) can be defined as the focus on meeting the needs and wants of a company’s customers. Customer orientation is a comprehensive, continuous analysis and evaluation of individual customer expectations as well as their internal and external transformation in output. In addition, it includes all interactions in the context of the relationship marketing concept with the objective to establish stable and profitable customer relationships [Bruhn 2003b, p. 15]. Customer orientation can be also considered as the proximity to customers [Homburg 2000]. However, customer orientation is not for free, but causes considerable costs and investments, such as administration (I 93), transaction (I 94), service (I 97), contact (I 100) or communication costs (I 99). Since maximal orientation is mostly not affordable, a company should determine an optimal degree of customer orientation by analysing its costs and benefit in order to improve the efficiency of customer orientation (see Figure 51a). On an individual level, different customers may need different degrees of orientation. The company has to focus on customers with a high information potential, i. e. with an intensive response rate (I 169), a high intention to dialog (I 157) and/or good cooperation behaviour (I 171 - I 173; see Figure 51b). b) Fuzzy Customer Orientation Portfolio 0 C1) Costly orientation (low costs, high benfits) (high costs, high benefit) C4) C3) Insufficient orientation Inefficient orientation (low costs, low benefit) (high costs, low benefit) 0 1 μ low costs Response rate (I 169; intention to dialog, I 157) 1 0 C1) Retain high customer orientation C4) C3) Retain low customer orientation Reduce customer orientation 0 1 μ high costs C2) Augment customer orientation Customer orientation (I 117) 1 C2) Efficient orientation Costs of customer orientation μ low benefit μ high benefit Benefit of customer orientation μ low response rate μ high response rate a) Fuzzy Cost-Benefit Analysis μ low orientation μ high orientation Figure 51: Fuzzy Cost-Benefit Analysis (a) and Portfolio of Customer Orientation (b) - 70 - Chapter 5: Fuzzy Customer Segmentation 5.1.6 Customer Value Customer orientation Customer value Customer satisfaction Customer loyalty Customer retention Customer equity Market value Shareholder Customers choose these products or services, which have the highest value for them. That means “customers are value-maximisers, within the bound of search costs and limited knowledge, mobility and income. They form expectations of value and act upon them. Then they compare the actual value they receive in consuming the product to the value expected, and this affects their satisfaction and repurchase behaviour” [Kotler et al. 2005, p. 463]. The customer delivered value is defined as the difference between total customer value and total customer cost of a marketing offer, i.e. the ‘profit’ to the customer. Total customer value is thereby the total of the entire product, services, personnel and image values that a buyer receives from a marketing offer and total customer cost is the total of all the monetary, time, energy and psychic costs associated with a marketing offer [Kotler et al. 2005, p. 464]. According to Kotler’s explanations, customer value (I 124) is defined here as value creation from a customer perspective. This customer point of view of customer value is common in CRM literature (see [Rust et al. 2000, Eggert 2006, Helm and Günter 2006, Bauer et al. 2006, Belz and Bieger 2006]). In addition, a distinction is made between the basic value (e.g. technical-functional value) and the added-value (socio-psychological value). It is a strategic task to identify, create, maintain and control important customer value drivers and to manage them by portfolios analysis. Since customer value contributes to customer satisfaction, drivers of customer value and satisfaction often go hand in hand. A selection of customer value and satisfaction drivers is listed in Table 14. More value factors are shown in Appendix 3. Table 14: Drivers of Customer Value and Satisfaction Customer Value Drivers ; Company’s reliability ; Company’s (core) competencies ; Company’s expertise / knowledge ; Company’s experience ; Company’s network ; Goals, goal compatibility ; Bonds (structural, social, economic) Customer Satisfaction Drivers Service specific criteria of customer satisfaction Product specific criteria of customer satisfaction Reaction to customer problems ; Ability to meet specifications Reactivity and flexibility ; Failure, error and rejection rate Availability of contact persons ; Availability of products Convenience and accuracy of documentation ; Constant quality and reproducibility Reliability ; Sales assistance Frequency of delivery ; Product literature Delivery within the agreed time ; Technical assistance Terms of payment and financing ; Maintainability and longevity Handling of complaints ; Completeness of delivery Service quality and innovation ; Product training Warranties ; Product development ;: Nominal fuzzy classification possible ;: Discrete fuzzy classification possible Price, monetary sacrifices Quality (of products or services) Technical values Functional values Psychological or emotional values Social values (added-value) Relationship values ; ; ; ; ; ; ; Product innovation and creativity Individualisation or personalisation Accuracy, flexibility, efficiency Coordination and organisation Reputation, image, status, prestige Problem identification Empathy and trust ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; Source: adapted from [Leino 2004, pp. 45f, Belz and Bieger 2004, p. 101, Waibel and Käppeli 2006, p. 172] - 71 - Chapter 5: Fuzzy Customer Segmentation 5.1.7 Customer Satisfaction Customer orientation Customer value Customer satisfaction Customer retention Customer loyalty Customer equity Market value Shareholder Customer satisfaction is considered as a Key Performance Indicator (KPI) of corporate success. From the company’s point of view, customer satisfaction can be considered as the company’s ability to fulfil the economical, emotional and psychological needs of its customers. From the customer’s point of view, customer satisfaction as an attitude can be defined as the fulfilment of customers’ requirements or needs. Customer (dis)satisfaction with a product (I 128), service (I 129) or the company itself (I 126), depends on the customer’s comparison of ex- pectations (I 125) and perception of experience. Dissatisfied customers often migrate to competitors and to their offers. This does not only result in lower sales, but often leads to negative word of mouth. Empirical studies show that only 5% of the dissatisfied customers complain, but they share their experiences in average with ten other persons and 90% do not buy the company’s products anymore [Waibel and Käppeli 2006, p. 171]. Several methods are used to track satisfaction: companies can install complaint or suggestion systems (e.g. customer hotlines, suggestion boxes, complaint forms) or make periodic satisfaction surveys. Thereby it is important to ask customers about their intention to recommend a product or service (I 151; “would you recommend this product or service to friends?”). With fuzzy classification, the assignment of a customer to one class or several classes is more precise. This enables, for instance, the analysis of the customer’s overall (dis)satisfaction in relation to the satisfaction with a certain product X (see Figure 52a). Regarding the overall satisfaction and the customer’s willingness or intention to switch, four different basic strategies are defined in Figure 52b. With fuzzy classification, customers can be assigned differentiated 1 0 C1) Overall satisfaction C4) C3) Overall dissatisfaction Satisfaction with product X only 0 1 Customer satisfaction (I 126) μ satisfaction C2) Dissatisfaction with product X only b) 1 0 C1) Retain satisfaction Bind customers C4) C3) Reduce dissatisfaction Improve satisfaction 0 1 μ dissatisfaction with X μ satisfaction with X C2) μ unwilling to switch μ willing to switch Figure 52: Examples of Fuzzy Classified Customer Satisfaction Portfolios - 72 - Willingness/intention to switch (I 140,I 141) μ dissatisfaction μ satisfaction Customer satisfaction (I 126) μ dissatisfaction a) Satisfaction with product X (I 128) to the basic strategies and can be managed according to their satisfaction level. Chapter 5: Fuzzy Customer Segmentation 5.1.8 Customer Loyalty Customer orientation Customer value Customer satisfaction Customer loyalty Customer retention Customer equity Market value Shareholder It is well documented in literature on marketing that higher customer satisfaction leads usually to higher loyalty. Customer loyalty (I 134) is defined here as the behaviour customers exhibit, when they make frequent repurchases of products of the company or plan to do so, and if they intend to recommend the company to others. Different methods and approaches are discussed in literature, how to measure loyalty. Directly measurable indicators for loyalty are: number of repurchases (I 56), repurchase intentions (I 55) and cross buying (I 50 - I 54) intention to recommend (I 151) and number of recommendations (I 152) duration and intensity of the customer relationship (I 147, I 148) share of wallet (i.e. the percentage of a customer’s requirements of a product or service category that are fulfilled by a particular product or service of the company; I 38 - I 41) RFM method discussed in Section 3.5: “Recency of last purchase” (I 27), “Frequency of purchase” (I 28) and “Monetary value” (I 29) or the u t Repeat buyer (I 8) Customers (I 7) First-time buyer (I 6) Brown Prospective customers (I 1) r Product interesent q Advertising contacted n m Potential buyer (I 1) Pre-buying phase o Miller Sequence buyer (I 8) s Z μ regular buyer Regular buyer (I 9) Smith Contacted Intesive user Ford User Light user Potential to contact μ usage potential w v After-buying phase loyalty ladder, which classifies customer loyalty into different steps (m-w in Figure 53) Usage notice Potential user Usage potential Source: adapted from [Kreutzer 1992, p. 335, Neckel and Knobloch 2005, p. 28, Krafft 2002, p. 66] Figure 53: Loyalty Ladder - 73 - 0 1 Chapter 5: Fuzzy Customer Segmentation According to the loyalty ladder, regular customers or regular buyers (I 9) are the most loyal customers. Most companies in business practice analyse their regular customers (see [RudolfSipötz 2001, pp. 67ff]): the main criteria for the definition of a regular customer are customer turnover (I 31), contribution margins (I 69 - I 73), customer penetration (I 38), share of wallet (I 39), number and rhythm of purchases (I 20; I 25; I 56) and the duration of the relationship (I 147). To augment loyalty is essential to enrich customer relationships, e.g. by a high degree of added-value, trust, exchange of information or cooperation ([Homburg 2001]; see Figure 54a). Another widely used way to bind customers and improve future financial performance at the firm level is to augment switching costs (Figure 54b). Switching costs place a technical, functional, contractual, financial, psychological or emotional burden on the customer, who intends to switch away from the offered products or services, or from the company itself, to a competitor. Switching costs include all costs of determining the relationship to the company and setting up a new one until it provides the same benefit (see [Büschken 2004, Dikolli et al. 2006]). a) Higher Loyalty through Enriched Relationships b) Higher Retention through Lock-in Effects Ford 1 0 Naked relationship Forrester 00 1 C4) Smith C3) Brown No loyalty Ford 1 Latent loyalty Forrester 00 1 μ low attachment μ high turnover True loyalty C2) O’Connor Improve loyalty C4) Smith μ low turnover Pseudo loyalty C1) Miller Attachment (I 132) μ few repurchases μ many repurchases Spencer μ satisfaction Turnover or sales (I 31) Repurchases (I 56) C2) μ dissatisfaction d) Fuzzy Classified Loyalty/Turnover Portfolio c) Fuzzy Classified Loyalty Portfolio O’Connor Forrester Low switching costs μ satisfaction μ dissatisfaction O’Connor Ford 1 0 1 High switching costs Smith Miller Don’t invest Ford 1 0 Commit customer C3) Augment turnover Brown 0 1 μ high attachment C1) Miller Customer loyalty (I 134) μ low loyalty O’Connor Brown Customer satisfaction (I 126) Enriched μ low retention Miller Smith Brown μ high retention Customer loyalty or retention (I 137) Customer satisfaction (I 126) μ high loyalty Customer loyalty (I 134) μ low loyalty μ high loyalty Source: adapted from [a) Homburg 2001, p. 50; b) Büschken 2004, p. 15; c) Bauer et al. 2006, p. 132; d) Werro et al. 2005a, p. 10] Figure 54: Examples of Fuzzy Classified Customer Loyalty Portfolios - 74 - Chapter 5: Fuzzy Customer Segmentation In Figure 54c, fuzzy classification facilitates to identify and segment the true loyal customers (Miller), to distinguish pseudo loyal clients (O’Connor) from more promising ones (Spencer), latent loyal customers (Forrester) from quite loyal ones (Brown) or separate very disloyal (Ford) from more loyal customers (Smith). With the fuzzy classified portfolio in Figure 54d, it can be distinguished between customers to invest (Smith) or not (Ford), if loyalty (O’Connor) or turnover (Brown) has to be improved or which customers have to be committed (Miller). Dynamically, fuzzy classification provides valuable information by analysing, evaluating and controlling individual effects of retention and loyalty programs or of switching barriers. In addition, fuzzy classification enables the offering of individual and personal loyalty rewards, like personal discounts (see Werro et al. 2005b), bonus points, special offers or presents. Customer clubs, frequent flyer programs, communities and account or store cards are other examples of incentives for customers to stay loyal and repurchase by the company. 5.1.9 Customer Retention Customer orientation Customer value Customer satisfaction Customer loyalty Customer retention Customer equity Market value Shareholder Customer retention (I 137), in a marketing sense, means holding on to customers [Peelen 2006, p. 239]. In contrast to loyalty, customer retention can be defined from a customer- and from a company point of view. Retention from the customer’s point of view exits, if a customer has certain reasons to repurchase from the company. However, customer retention is usually defined from the company’s point of view [Homburg and Bruhn 2006, Reinecke and Dittrich 2006], and contains all actions, which lead to customer repurchases or cross-buying and avoid that customers migrate to competitors. It can be distinguished between real and intentional customer retention with different determinants shown in Figure 55. Customer retention (I 137) Real customer retention (q) Intentional customer retention (p) Repur- Recom- Cross- Purchase Customer Migrated Repurchase Intention to Cross-buy- Price chases mendations buying intensity penetration customers intention recommend ing intention premium (I 51) (I 61) (I 56) (I 152) (I 26) (I 38, I 39) (I 54) (I 55) (I 10) (I 151) Source: adapted from [Bruhn 2003a, p. 104] Figure 55: Determinants of Customer Retention As customer retention is crucial to augment customer equity and profit, CRM and marketing require an adequate number of relevant retention indicators to manage and control different levels of customer retention: customer attitudes (o in Figure 56), intentional customer retention (p), real customer retention (q) and the retention results (r). - 75 - Chapter 5: Fuzzy Customer Segmentation q Real customer retention p Intentional customer retention o Attitude n Investments in customer retention Repurchases (recency, frequency, rhythm; I 20-I 28), cross-/upbuying (I 50-I 53), share of wallet (I 39), payment behaviour (I 66), recommendations (I 56), duration of relationship (I 147) Repurchase intentions (I 55), cross-buying intentions (I 54), intention to recommend (I 151), intention to switch (I 141), intention to dialog (I 157), intention to cooperate (I 171) Perceived product (I 118), service (I 120), relationship quality (I 149) or price-performance ratio (I 122), customer satisfaction (I 126), commitment (I 131), trust (I 133), image (I 115) Customer retention costs (I 89) or total customer costs (I 102): marketing (I 101), administration (I 93), transaction (I 94), contacts (I 100), sale (I 95), logistic (I 96) or after sales (I 98) costs Retention in case of habitualised purchase behaviour Customer Investment Indicators (CII) Retention results Category of indicator Customer Relationship, Information, Recommendation and Cooperation Indicators (CRI, CInfI, CReI, CCR) r Turnover (I 31), cash flow (I 30), contribution margins I-IV (I 70 - I 73), customer gross (I 75) or net profit (I 76), customer equity (I 79), number of customers (I 7), market share (I 43) Customer Performance Indicator for Revenue and Profitability (CPIP) Controlling level of retention Indicators of customer retention Source: adapted from [Reinecke and Dittrich 2006, p. 329] Figure 56: Controlling Level and Indicators of Customer Retention Investments in customer retention (n in Figure 56) can be measured easily by customer investment indicators (e.g. retention costs; or total customer costs). However, the evaluation of retention indicators about attitudes and intentional customer retention (e.g. repurchase or cross-buying intentions) on the controlling level o and p, is difficult, since they are hidden, implicit, inconstant over time and differ from customer to customer. Nevertheless, intentions determine real customer retention (q; like the number of repurchases or cross-buying) and the retention results (r), which can be analysed by customer performance indicators for revenue and profitability (e.g. customer turnover or profit). In case of habitualised purchasing behaviour, a customer who, for instance, has always bought his bread from the same bakery, can be seen as bound, although he may have no attitudes or clear intentions. Combining any customer retention indicators of the five controlling levels of customer retention (o↔p/q/r; p↔q/r), fuzzy portfolio analysis enables the classification of indicators of customer attitude, intentional or real customer retention and the evaluation of retention results. Considering attitude/intentional retention portfolios, it is very advisable to reduce negative attitudes (e.g. dissatisfaction) of customers towards the company, who intend to share their negative feelings with many other persons (C2 in Figure 57a). CRM should set incentives (C3) and maintain customers with positive attitudes and high intentional retention (C1). However, since even very positive customer attitudes (like high satisfaction) towards the company and its products or services do not necessarily lead to higher real customer retention (e.g. in the case of variety seeking in Figure 57b), fuzzy classified retention portfolios can be useful to identify very delighted customers to retain (Miller) or real uncertain customers (Ford). Intentional/real customer retention portfolios (Figure 57c) provide valuable information whether customers really do repurchase or only intend to do. - 76 - Chapter 5: Fuzzy Customer Segmentation 0 C4) C3) Don’t care and don’t invest Augment intention (set incentives) μ dissatisfied C4) Smith 0 Variety seekers (to monitor) (to bind or not) 0 1 μ satisfied C3) Uncertain customers Ford a) Fuzzy Attitude/Intentional Retention Portfolio μ dissatisfied μ satisfied b) Fuzzy Attitude/Real Retention Portfolio o↔p Investments inn customer retention (to invest) Brown 1 0 1 (to skim) C1) Miller Delighted customers o↔q Attitude o Intentional p customer retention Real customer q retention Retention results p↔r p↔q c) Fuzzy Intentional/Real Retention Portfolio 1 0 (to skim) (to retain) C4) C3) Little customer retention High customer intentional retention (don’t invest) (to realise) 0 1 μ low intention μ high profits C1) High customer retention Retention results: customer profits μ low profits C2) High real customer retention d) Fuzzy Real Retention/Results Portfolio Repurchase intention (I 55) and Cross-/up-buying intentions (I 54) μ few repurchases μ many repurchases Repurchases (I 56) and cross-/up-buying (I 50-I 53) r C1) Acquire, diversify, innovate Defend customer excellence C4) C3) Consolidate Reduce costs customer/ proor improve efficiency duct portfolio 1 0 0 1 μ high intention C2) Real customer retention μ low intention 1 Maintain intention C2) Locked-up customers Customer satisfaction (I 126) C1) Repurchases (I 56), share of wallet (I 39) μ few repurch. μ many repurchases C2) Reduce intention (improve satisfaction) Customer satisfaction (I 126) μ high intention Intention to recommend (I 151) μ low retention μ high retention Figure 57: Fuzzy Classified Portfolios of Customer Retention Indicators Attitudes and behavioural intentions are interesting psychological constructs, but what counts in business practice is real customer retention (i.e. many repurchases, cross-/up-buying, longterm relationships, etc.) and retention results. Possible retention results are customer turnover (I 31), contribution margins (I 70 - I 73) and customer profits (I 75, I 76). A company which does not realise high profits in the long term is not successful, even if market shares are high and all customers loyal (zero migration; C3 in Figure 57d). In such situations, the organisation may have to be restructured, customer costs to be reduced or the efficiency to be increased to achieve customer excellence (in C1). A company in a highly competitive and dynamic market with low customer retention (C2), is forced to constantly acquire new customers, to diversify its product or service portfolio and/or to innovate in order to retain high customer profits. - 77 - Chapter 5: Fuzzy Customer Segmentation 5.1.10 Repurchases Customer orientation Customer value Customer satisfaction Customer retention Customer loyalty Customer equity, CLV Market value Shareholder Repurchases Satisfied, loyal or bound customers are more likely to repurchase the same products or service from a company. As a result, customer repurchases (I 56), repurchase intentions (I 55) or the probability of repurchases (I 57) are meaningful indicators for customer loyalty and retention. The more often a customer repurchases from the company, the higher is the customer equity or Customer Lifetime Value (CLV). To increase or retain repurchases, it is a strategic task to maintain customer satisfaction or loyalty, and to augment the ease of purchase, e.g. by a high availability or good distribution of products and services. As discussed in the RFM example in Section 3.5, purchase incentives or loyalty programs may raise the number, frequency and monetary value of repurchases. In addition, reminders, catalogues, brochures, newsletters or e-mails can stimulate customers to buy again or more often (see Figure 58). b) 0 Augment repurchases Retain customer C4) C3) Don’t invest Augment monetary value μ very recent C1) 0 1 Recency (of last purchase; I 27) 1 0 C1) Augment frequency Retain customer C4) C3) Don’t invest Reactivate customer 0 1 μ few repurchases μ many repurchases C2) Frecency of purchases (I 28) 1 C2) Number of repurchases (I 56), probability of repurchases (I 57) μ low value μ high value Monetary value (I 29) μ long ago a) μ rare μ frequent Figure 58: Examples of Fuzzy Classified Repurchase Portfolios 5.1.11 Add-on Selling Customer orientation Customer value Customer satisfaction Customer loyalty Customer retention Customer equity, CLV Market value Shareholder Add-on selling A strategic topic and instrument of CRM is add-on selling. Add-on selling can be defined as “the activity associated with selling any additional products or services to current customers” [Blattberg et al. 2001, p. 95]. Add-on selling includes down-selling (the selling of less valuable or cheaper products or services; I 50), cross-selling (of other, similar or new products; I 51) and up-selling (more expensive or valuable products of the company; I 53). - 78 - Chapter 5: Fuzzy Customer Segmentation b) High cross-selling potential (I 52) C4) C3) 0 Exploitation μ high potential Retention Disinvestment 1 C1) 0 1 μ low loyalty Cross-selling potential (I 52) C2) 1 0 C4) C3) Downgrading (to weaken relationship) Absorption (to maintain relationship) 0 1 μ high loyalty C1) Penetration Upgrading (to provide (to strengthen cross- & uprelationship) selling offers) Cross-selling (I 51) or up-selling (I 53) μ low potential C2) Customer loyalty (I 134) or Customer retention (I 137) μ high potential Customer potential (I 83) μ low potential a) μ low cross-selling μ high cross-selling Source a): adapted from [Bruhn and Georgi 2006, p. 47] Figure 59: Examples of Fuzzy Classified Add-on Selling Portfolios By analysing customer loyalty (I 134) or retention (I 137), the potential for turnover or profit (I 83), customers needs, the purchased product mix by the company or by the competitors (I 58) and the purchase behaviour in general, the cross-selling potential (I 52) can be evaluated. For promising customers or customer segments with high cross- or up-selling potential (C1 in Figure 59a; C1 and C2 in Figure 59b), customer penetration strategies (to provide offers) or upgrading strategies (to strengthen relationships) have to be formulated and implemented. If customers do not buy many different products and have rather low cross-buying potential, customer relationships should be managed less cost-intensive (C4: downgrading). 5.1.12 Share of Wallet Customer orientation Customer value Customer satisfaction Customer loyalty Customer retention Customer equity, CLV Market value Shareholder Share of wallet The customer performance indicator share of wallet (I 39) measures the share of the customer’s expenditures for a specific product or services in relation to the total expenditures. Following example explains the idea of the share of wallet: if a customer purchases the total amount of a product A by the company 1 in period 1, he has a maximum share of wallet of brand A (see Figure 60a). In period 2, the customer may switch to brand B by the company 2. He has now a maximum (100%) share of wallet of brand B, and a minimal one (0%) of A. However, the customer does not necessarily choose A or B ("crisp" choice in Figure 60a), but rather choose partially A (10%), partially B (80%) and partially C (10%). This example of [Rust et al. 2000] shows: the idea of fuzzy logic can be easily applied to the concept of share of wallet to analyse the "fuzzy" choices of a customer. As exemplified in Figure 60b, in period 2 the share of wallet of brand B was increasing and this one of brand A decreasing. - 79 - Chapter 5: Fuzzy Customer Segmentation a) "Crisp" (Sharp) Choice Maximum share of wallet of brand A (by company 1) Brand A Brand B 0% A B Period 1 Period 2 Period 100% Maximum share of wallet of brand B (by company 2) b) "Fuzzy" Choice (share of wallet) Increasing share of wallet of brand B (by company 2) Brand A & B 100% B B A 0% Period 1 Period 60% Brand C C A Period 2 Decreasing share of wallet of brand A (by company 1) Source cartoon: [Rust et al. 2000, p. 43] Figure 60: Crisp (a) and Fuzzy (b) Choice It might be interesting to compare the share of wallet fuzzily with the level of customer penetration (I 38; the percentage of all demanded products bought from the company) to define penetration or add-on selling strategies (in Figure 61a). Since a company is very dependent (I 136) of a customer with a high market share (I 42), it has to follow intensive customer acquisi- tion and penetration strategies in order to increase the own market share (see Figure 61b). b) Retain customer C4) C3) Penetrate customer 1 0 C1) Add-on selling 1 0 1 Market share of customer (I 42) 0 C1) Intensive retention C4) C3) Moderate acquisition penetration Moderate retention 0 1 μ low share of wallet μ high share of wallet C2) Intensive acquisition and penetration μ low share of wallet μ high share of wallet Figure 61: Examples of Fuzzy Classified Share of Wallet Portfolios - 80 - Share of wallet (I 39), or customer penetration (I 38) C2) Augment share of wallet (of product X) Share of wallet (I 39) μ low penetration μ high penetration Customer penetration (I 38) μ low market share μ high market share a) Chapter 5: Fuzzy Customer Segmentation 5.1.13 Turnover Customer orientation Customer value Customer satisfaction Customer retention Customer loyalty Customer equity, CLV Market value Shareholder Turnover, sales and cash flows According to empirical studies, the financial indicators customer turnover, sales or revenues (I 31) are regularly measured in most of the companies (see for instance [Reinecke 2004]). This kind of data can be gathered easily from the accounting or marketing department or is available in an information system. To classify customer turnover sharply is problematic, since only small changes of turnover or sales may cause different classifications of customers. However, a fuzzy classification of customer turnover can be one- or multidimensional. The fuzzy classification in Figure 62a, described by [Meier et al. 2005], combines the attribute turnover with the ‘punctuality of payment’ (I 63) and defines four basic strategies. In Figure 62b, a dynamic fuzzy classification with the attribute ‘cumulative turnover’ (I 34) and the negative or positive ‘growth of turnover’ (I 35) is considered. A sharp classification would be a mistake, as the examples of Smith and Brown show again; although they have approximately the same values, Brown is labelled as a ‘top’ (C1) and Smith as a ‘flop customer’ (C4). Fuzzily, the customers are named and managed more sophisticated and manifold. b) Commit customer C4) C3) Don’t invest 1 0 C1) Augment turnover μ unpunctual C1) Top Customers (to maintain) Miller Brown Flop customers (not to invest) C3) Churn customers (to recover) Ford 0 0 1 μ punctual C2) Growth customers (to invest) C4) Smith 1 0 1 Growth of turnover or sales (I 35) Cumulative turnover (I 34) μ low turnover C2) Improve punctuality of payment Punctuality of payment (I 63) μ high turnover Turnover (I 31) μ high neg. growth μ high pos. growth a) μ low cum. turnover μ high cum. turnover Source: a) adapted from [Meier et al. 2005, p. 20] Figure 62: Examples of Fuzzy Classified Turnover Portfolios The evaluation of customer’s turnover or revenue does not allow making any statement about the customer’s costs or profitability. An isolated consideration of the customers’ monthly or annual turnover may lead to misinterpretations and has to be supplemented with the following discussed indicators: customer’s contribution margins and customer gross or net profit. - 81 - Chapter 5: Fuzzy Customer Segmentation 5.1.14 Contribution Margins Customer orientation Customer value Customer satisfaction Customer retention Customer loyalty Customer equity, CLV Market value Shareholder Contribution margins Since cost-intensive customers with high turnover are not necessarily profitable, customer contribution margin accounting is required to determine the profitability of the customers. The main problem in doing so is to identify, allocate and to trace total customer costs (I 102), such as administration (I 93), transaction (I 94), sales (I 95), logistic (I 96), service (I 97), after sales (I 98), communication (I 99), contact (I 100) or marketing (I 101) costs. General or overhead costs which are not, or only partly traceable to a customer, are not accounted in the example of multi-level customer contribution margin accounting shown in Figure 63a, nevertheless they should be. However, customer-related allocation of costs is necessary in order to calculate the profitability of a customer. Therefore, a customer-oriented calculation of direct costs is useful. With the calculation scheme shown in Figure 63a, four different customer contribution margins I (I 70), II (I 71), III (I 72) and IV (I 73) can be calculated and evaluated fuzzily. = Customer net sales revenue – Costs of goods/services sold = Customer contribution margin I – Customer-driven marketing costs (I 101; e.g. mailings, calls, trials, card) = Customer contribution margin II – Customer-driven sales costs (I 95; e.g. sales force, ordering, billing) = Customer contribution margin III – Customer-driven service and logistic costs (I 96, I 97, I 98); e.g. after sales service, delivery of goods, helpdesk) = Customer contribution margin IV High With fuzzy classification, customers can be better analysed and segmented by their contribution margin 500 200 Medium 750 Brown Miller Turnover (I 31; in €) – customer-related revenue reductions (e.g. volume discount, cash discount) 1000 100 50 Smith Low Customer gross sales revenue per period ≥1250 0 -50 -100 -150 Negative a) Calculation Scheme for Customer Contribution Margins Customer contribution margin I-IV (I 73; in €) μ negative contribution margin μ positive contribution margin high contribution margin b) Correlation between Annual Contribution Margin I IV and Turnover per Customer Ford -200 1 Low 0 0 250 500 Medium 750 1000 High 1250 1500 3000 6000 9000 0 1 μ low turnover Source calculation scheme: adapted from [Bruhn and Georgi 2006, p. 40, Bauer et al. 2006, p. 173] Figure 63: Customer Contribution Margin Accounting - 82 - μ high turnover Chapter 5: Fuzzy Customer Segmentation As shown in Figure 63b, Ford and many other customers with low turnover have a lightly negative contribution margin. This means that a high share of the customers is not profitable. Usually, the contribution margins and their deviation rise with increasing turnover. Since Miller causes higher costs, he is less profitable than Mr. Brown, despite higher turnover. A detailed margin accounting can provide important evidence for different customer costs and customer profitability and therefore for the evaluation of customer attractiveness (I 82). In Figure 64, four customer contribution margins portfolios give valuable information about customer costs of marketing (I 101), sales (I 95), service (I 97) or logistic (I 96), about the level of the customer contribution margins I to IV (I 70 - I 73), and about simple strategies. a) Fuzzy Contribution Margin I Portfolio Customer net sales revenue (I 31) b) Fuzzy Contribution Margin II Portfolio C3) 1 0 1 0 1 1 C4) C3) Consolidate product or customer portfolio Reduce sales costs (I 95) 00 1 μ low margin II μ low margin IV μ high margin IV C1) Retain customer and product C3) Consolidate product or cusomer portfolio Reduce marketing costs (I 101) μ low margin I μ high margin I Contribution margin IV (I 73) Contribution margin II (I 71) μ low margin III μ high margin III 1 C2) C4) d) Fuzzy Contribution Margin IV Portfolio Contribution margin III (I 72) Increase contribution margin II C1) Retain customer and product 00 μ low sales revenue μ high sales revenue c) Fuzzy Contribution Margin III Portfolio C2) Increase contribution margin I Contribution margin I (I 70) C4) Consolidate Reduce costs product or cus- of goods or stomer portfolio services μ high margin II C1) Retain customer and product 1 C1) Increase contribution margin III Retain customer and product C4) C3) Consolidate Reduce product or cus- service/logistic omer portfolio costs (I 97,98) 00 1 μ high margin II C2) μ low margin III Contribution margin III (I 72) μ low margin I C2) Increase turnover or sales Contribution margin II (I 71) μ low margin II μ high margin I Contribution margin I (I 70) μ high margin III Figure 64: Fuzzy Classified Customer Contribution Margins Portfolios In addition, fuzzy classification is useful for identifying and separating valuable customers with high contribution margins from unattractive ones with low or lower margins, and for managing these customers adequately by CRM and marketing. - 83 - Chapter 5: Fuzzy Customer Segmentation 5.1.15 Profitability Customer orientation Customer value Customer satisfaction Customer loyalty Customer retention Customer equity, CLV Market value Shareholder Profits According to [Kotler et al. 2005, p. 474], a profitable customer is a person, whose revenues (I 31) over time exceed the company’s costs of attracting (I 87), selling (I 95) and servicing (I 97) that customer. Customer gross profit (I 75) is defined here as the customer’s total turnover (I 31) minus total customer’s costs (I 102). Customer net profit (I 76) additionally considers taxes, interests, depreciations or other expenses. ‘Customer profitability’ (I 78) and ‘customer retention’ (I 137), both measured either at a customer, customer segment or at the enterprise level, and the ‘number of customers’ (I 7) can be linked to a multidimensional fuzzy classification (in Figure 65b). Depending on the profitability and retention of a customer (segment), and on the number of customers, Figure 65a defines the directions of growth. In addition, the development (growth) of all indicators are classified dynamically and fuzzily in Figure 65c. C3) low retention high retention high number low number Customer retention C1) Exploit channel or C5) Defend marketing opportunities C2) Offer innovation, cut C6) Improve customer price, bind customers loyalty or swichting cost C7) Reduce customer C3) Consolidate costs, raise price product portfolio C4) Restructure C8) Consolidate business customer base Source strategies of a): adapted from [Plaster and Alderman 2006, p. 3] Description of the Development 2005-2007 n In 2005, the retention rate of the company o p q r has decreased and the company lost many customers, although profits increased. CRM reacts and follows fuzzily strategy C2): prices are reduced and loyalty programs launched in order to reduce to churn rate. Due to lower prices, profits decreased in 2006. However, customer retention and the number of customers strongly increased. To raise profits again, management reduces production, marketing and customer costs. As a result, profits were increasing again in 2007 and the number of customers and customer retention remain high. C6) C5) C2) C1) C8) 1 Number of customers (I 7) C7) Number of customers μ high profits C8) C4) Customer profitability (I 78) C5) C1) C7) C4) μ low profits C2) b) Fuzzy Classification of Customer Profitability C3) μ high number μ low number 00 Customer retention (I 137) μ low retention rate μ high retention rate c) Dynamic Fuzzy Classification of Growth Development of customer profitability (I 77) μ declining profits μ increasing profits low profits high profits Customer profitability C6) 1 r n 2005 2005 o 2007 2007 q 2006 2007 2006 2005 00 2005 2007 μ decreasing rate 2006 μ increasing number μ decreasing number Development of the customer retention μ increasing rate rate Figure 65: Fuzzy Classification of Customer Profitability - 84 - 2006 p Development of the number of customers a) Defining the Directions of Growth Chapter 5: Fuzzy Customer Segmentation To augment the number of customers, the company should exploit channel or marketing opportunities in the case of high customer retention and profits (C1 in Figure 65a) or offering innovations, cutting the prices and bind customers, if customer retention and the number of customer is low (C2). If profits are low despite high retention and a high number of customers (C7), customer costs have be to reduced and prices to be raised. If the number of customers (C3) or customer retention is low as well (C8), the product portfolio or customer base has to be consolidated. Businesses have probably to be restructured, if all three indicators are low (C4). Using these three strategic customer indicators and fuzzy classification, the performance of a customer, of a fuzzy segment or of the whole company can be classified precisely in order to define and implement the different strategies of growth. However, the company has different opportunities to achieve customer growth. For instance, it can either follow the profit maximising growth strategy, the market penetration or the customer retention strategy, or all strategies simultaneously (see Figure 66). The company has to choose the strategy or axis that provides the best opportunity for profitable growth. Understanding fuzzily the size and shape of the cubes, CRM has to follow these growth strategies with the best future theoretical state ("could be") and practical condition ("should be"). The main advantage of this approach of customer strategy definition and implementation is that it can be applied with any kind of strategic customer indicators, which can be dynamically and fuzzily analysed, evaluated and controlled by managers or by CRM software. a) "All-in-One" Customer Growth Strategy b) Customer Profit Maximising Growth Strategy Future state "should be" operations Current state Number of customers Customer retention All-in-one strategy Customer profitability Profit-maximising strategy Customer profitability Future state "could be" operations Current state Number of customers Current state Number of customers Number of customers Customer profitability Customer profitability Customer retention Current state Customer retention Customer retention strategy Customer retention Source: a) adapted from [Plaster and Alderman 2006, p. 2] c) Market Penetration Growth Strategy d) Customer Retention Growth Strategy Figure 66: Customer Growth Strategies - 85 - Chapter 5: Fuzzy Customer Segmentation 5.1.16 Customer Equity and Customer Lifetime Value (CLV) Customer value Customer orientation Customer satisfaction Customer loyalty Customer equity, CLV Customer retention Market value Shareholder Literature on customer equity increased quickly during the last years. However, there is no consistent definition of customer equity (see [Cornelsen 2000, Rudolf-Sipötz 2001, Blattberg et al. 2001, Rust et al. 2000, 2004, 2005, Rogers and Peppers 2005, Bauer et al. 2006, Reichold 2006, Günter and Helm 2006, Bejou and Gopalkrishnan 2006, Aksoy et al. 2007, Krafft 2007]). Customer equity can be defined as a synonym of Customer Lifetime Value (CLV; I 80): “A firm’s Customer Equity is the total of the discounted lifetime values of all of its customers” [Rust et al. 2000, p. 4]. Since it is difficult or even impossible to forecast or discount future customer cash flows, customer equity is here not understood as a discounted or a dynamic value. Customer equity (I 79), which can be considered as “the satisfaction of company with a customer” [Palloks-Kahlen 2006], is defined here as the current total monetary and non-monetary economical value of a customer for a company. Customer equity management is “a dynamic, integrative marketing system that uses financial valuation techniques and data about customers to optimise the acquisition of, retention of, and selling of additional products to a firm’s customers, and maximise the value to the company of the customers relationship throughout its life cycle” [Blattberg et al. 2001, p. 3]. Considering customer performance indicators of revenue and profitability, customer equity or CLV is higher with increasing customer (cumulative) turnover, contribution margins or net profit and customer retention. Figure 67a fuzzily segments customers with high, medium or low equity. As an aggregate, the total customer equity affects market value and market share, as well as the firm value and the shareholder value. If the customer equity share is low, the C3) 0 0 1 Augment customer C4) Low Medium customer customer equity equity (/CLV) (short-term) Market share (I 43,I 44) μ high share C1) Cumulative turnover (I 34) or profits (I 76) μ low retention μ high retention C2) Medium High customer equity customer (long-term) equity (/CLV) 1 b) Customer retention (I 137) μ low share a) 1 0 C1) Declining company Healthy company C4) C3) Sick company Growing company 0 1 μ low cum. turnover μ high cum. turnover C2) Customer equity (share; I 79) market share of a company declines or rests on a low level (see Figure 67b). μ low equity share μ high equity share Source: b) adapted from [Rust et al. 2000, p. 162] Figure 67: Examples of Fuzzy Classified Customer Equity Portfolios - 86 - Chapter 5: Fuzzy Customer Segmentation However, to augment customer equity (and market share/value), the company has to analyse on which customers it should focus and which customers should be bound in order to establish long-term, profitable relationships. The company has to evaluate all customers who are attractive, using, for instance, fuzzy portfolio analysis. The customer attractiveness/equity portfolio discussed by [Palloks-Kahlen 2006] consists of two dimensions (see Figure 68): the vertical axis indicates the level of ‘customer satisfaction with the company’ (I 126), or customer value (I 124) in a broader sense. In addition, the horizontal axis describes the ‘satisfaction of the company with a customer’, which can be seen as customer attractiveness (I 82) or customer equity (I 79), measured, for instance, by the customer contribution margins I-IV (I 70 - I 73). The six classes C1-C6 reflect different types of customers: regular buyers (I 9; C1 in Figure 68;) are convinced and profitable customers to maintain and suited for establishing long-term relationships. Satisfied customers (C5) in the "corridor for active CRM and customer retention" are to be developed by augmenting satisfaction and/or contribution margins. CRM, customer development and customer retention should focus on promising customers (of C2) in order to turn them into regular buyers. Customer satisfaction (I 126) or value (I 124) C2) Promising customer Ford μ low Disappointed and unprofitable customer Direction of differentiated customer development Smith C3) Profitable absorption customer high μ medium C5) Satisfied, but unprofitable customer Corridor for active customer retention (CRM) C4) Convinced, but unprofitable cu. C1) Regular buyer medium Area of long-term relationships C5) Satisfied but unprofitable cu. C2) Promising customer low μ high C1) C4) Convinced, but Regular buyer unprofitable Miller customer Brown C6) 1 Customer satisfaction (or value) C6) C3) Disappointed & Profitable unprofitable cu. absorption cu. low high Contribution margin I-IV Customer attractiveness (equity) Sharp classification (satisfaction of a customer with the company) Source: adapted from [Palloks-Kahlen 2006, p. 302] Customer equity (I 79) 00 (satisfaction of the company with a customer) measured by: contribution margins I-IV (I 70 - I 74) 1 μ low contribution margin μ high contribution margin Figure 68: Fuzzy Classified Customer Satisfaction/Equity Portfolio To distinguish sharply customers of these different classes is a problem, once again: why should Brown be labelled as ‘convinced but unprofitable customer’, but Miller as ‘regular buyer’, although they have nearly the same values? In addition, Ford should not be considered and managed just as ‘disappointed and unprofitable customer’ and Smith not only as ‘promising customer’. With fuzzy classification, the transitions between the different classes and CRM strategies become fluent and customer are mostly mixes of different classes and they can therefore be evaluated, developed and managed according to their real measured values. - 87 - Chapter 5: Fuzzy Customer Segmentation However, different drivers influence customer equity, and not only customer turnover or contribution margins. [Blattberg et al. 2001], for instance, define three drivers of customer equity: value equity (driven by quality, price, convenience), brand equity (determined by customer brand awareness, attitude, brand ethics) and retention equity (driven by loyalty, affininity, special recognition, treatment programs and others). An interesting conceptualisation and operationalisation of customer equity is discussed by [Rudolf-Sipötz 2001]. Using a factor analysis method, different determinants and customer performance indicators of the concept customer equity were empirically tested. The indicators and the different determinants (categories of potential) of customer equity are shown in Table 15. To improve customer performance and customer equity, diverse measures and actions of operational customer equity management can be implemented. Table 15: Determinants and Indicators of Customer Equity Market potential of customer Resource potential of customer Customer equity Determinant Customer Performance Indicator Customer contribution margin II (I 71) Profit Customer contribution margin III (I 72) potential Customer contribution margin IV (I 73) Development of sales/turnover (I 35) Development Potential of contribution margins (I 84) potential Probability of repurchases (I 57) and Phase in customer lifetime cycle Product portfolio by competitor (I 58) Cross-buying Need for diversification potential Cross-buying intention (I 54) Customer satisfaction (I 126) Loyalty Trust (I 133) potential Duration of relationship (I 147) Expertise for cooperation (I 172) Intention to cooperate (I 171) Cooperation Cooperation behaviour potential Potential cooperation topics (I 173) Lead user Product expertise (I 168) Intention to recommend (I 151) Number of recommendations (I 152) Reference potential Recommendation intensity (I 153) Potential reference recipients (I 155) Role as opinion leader (I 156) General intention to dialog (I 157) Information Number of complaints (I 164) potential Response rate (I 169) Number/quality of suggestions (I 164) Synergy Compound effect in customer base potential Actions of Equity Management ¨ Improvement of customer efficiency (I 108) (e.g. reduction of customer costs) ¨ Analysis of customer’s product mix (I 58) ¨ Analysis of needs and demand (I 117) ¨ Analysis and enhancement of customer value (I 124) and value drivers ¨ Analysis and enhancement of addedvalue, e.g. customising or personalisation ¨ Product and service bundling ¨ Diversification and innovation management ¨ Customer loyalty and retention programs ¨ Customer care and consulting (I 158) ¨ Customer relationship investments (I 87ff) ¨ Strategic alliances and networks ¨ Partnerships ¨ Lead user programs ¨ Cooperation programs (e.g. for R&D) ¨ Compatible information systems ¨ Suggestion boxes, etc. ¨ Member-get-member-/tell-a-friend-program (incentives for recommendations) ¨ Information and public relations ¨ Satisfaction and complaint management ¨ Customer surveys and questionnaires ¨ Hotline, call center, help/information desk ¨ Group discussions, conferences ¨ User groups ¨ Customer communities, clubs, cards, etc. ¨ Economics of scales (e.g. in R&D) ¨ Internal coordination (e.g. centralisation) Source: adapted from [Rudolf-Sipötz 2001, p. 95, 170, 186] [Rudolf-Sipötz 2001, pp. 192ff] undertakes a sharp classification to segment customers by defining a customer cube with the attributes ‘actual market potential of customer’ (i.e. the total direct, monetary value of a customer for the company), ‘future market potential’ and ‘resource potential’ (the total indirect, non-monetary value of a customer for a company). In Figure 69b, the customer equity cube is adapted to a three-dimensional fuzzy classification. - 88 - Chapter 5: Fuzzy Customer Segmentation C6) C2) C5) C1) C8) C4) C7) C3) low actual potential Future market potential of customer high actual potential high future potential low future potential Actual market potential of customers C1) Take along customers C5) Blue-chip-customers to augment share of wallet to invest and maintain C2) Selective customers C6) Perspective customer Don’t invest, but to maintain to invest and augment profit C3) Absorption customers C7) Potential customers to to skim, reduce costs invest & increase commitment C4) Renunciation custom. C8) Future customers Don’t invest, reduce costs Resource potential C6) C2) Future market potential of customer low resource potential high resource potential Resource potential μ low resource potential μ high resource potential b) Fuzzy Classification of Customer Equity a) Customer Segments and Strategies C5) C1) C8) C4) C7) C3) μ high future potential μ low future potential 1 0 Actual market potential of customer 0 μ low actual potential μ high actual potential to augment turnover Source: adapted from [Rudolf-Sipötz 2001, pp. 192ff] Figure 69: Three-Dimensional Fuzzy Classification of Customer Equity Classified fuzzily, the transitions between the classes and customer segments become fluent and the strategies of Figure 69a have to be adapted, aligned and personalised accordingly. Another, dynamic method to determine customer equity is the calculation of Customer or Prospect Lifetime Value (CLV, I 80; PLV, I 81). CLV portfolios should also consider monetary and non-monetary criteria, as shown in Figure 70a. Monetary CLV can be calculated by the formula of Figure 70c, qualitative criteria by a fuzzy scoring model or a cost-benefit analysis. C2) C1) To bind To commit Miller μ low CLV C4) Brown Don’t invest C3) Smith To monitor Ford 1 0 0 1 c) b) μ low retention PLV (Prospect Lifetime Value; I 81) 1 C1) Low investment in prospect C4) C3) Medium investment in prospect No investment in prospect 0 1 μ high retention Monetary criteria Customer Lifetime Value (CLV) 0 C2) High investment in prospect Intention to switch (I 141) or switching probability (I 142) non-monetary) μ high PLV monetary; μ low PLV μ high CLV CLV (I 80; Customer loyalty (I 134) or customer retention (I 137) a) μ low probability to switch μ high probability (Rt − Et ) t t =0 (1 + i ) n Revenues: customer turnover (I 31), cum. turnover (I 132), cash flow (I 30), monetary value (I 29); etc. Expenses: acquisition (I 87) retention (I 89), service (I 97), marketing (I 101), total customer (I 102) costs Non-monetary criteria Fuzzy Customer recommendation (I 151-I 156), information scoring model (I 157-I 170) and cooperation (I 171-I 173) indicators CLV = ∑ Rt = Total customer revenues (cumulated customer turnover; I 34) Et = Total customer expenses (total customer costs; I 102) t = Duration of customer relationship (I 147) i = Discount rate Figure 70: Fuzzy Classified Customer (a) and Prospect (b) Lifetime Value Portfolios - 89 - Chapter 5: Fuzzy Customer Segmentation [Rust et al. 2000, p. 191] define a four-tier system to classify customer equity (see Figure 71): The platinum tier describes the company’s most profitable customers (I 78), typically those who are heavy and regular users (I 22) of the product, are not overly price sensitive (I 60), are willing to invest in and try other or new offerings (I 51), and are committed (I 131) or loyal (I 134) customers of the company. The gold tier differs the platinum tier in that profitability levels are not as high, perhaps because the customer want price discounts (I 37) that limit the contribution margin I to IV (I 70 - I 73) or they are not as loyal. The iron tier contains essential customers who provide the volume needed to utilise the company’s capacity, but their spending levels, loyalty and profitability are not substantial enough for special treatment. The lead tier consists of customers who are costly for the company. They demand more attention than they are due given their spending and profitability and are sometimes problem customers, complaining about the firm to others (I 155), tying up the firm’s resources (I 102). Brown Gold What (fuzzy) segment spends more with us over time, costs less to maintain and spreas positive word of mouth? Smith Iron Least profitable customers Smith Ford Lead Miller Brown Ford What (fuzzy) segment costs us in time, effort, and money yet does not provide the return we want? What fuzzy segment is difficult to do business with? μ least profitable Platinum Miller μ most profitable b) a) Most profitable customers 0 1 Source a): [Rust et al. 2000, p. 193] Figure 71: Sharp (a) and Fuzzy Classified (b) Customer Equity Pyramid However, it is problematic to label customers sharply just as ‘platinum’, ‘gold’, ‘iron’ or ‘lead’, since the definitions of these classes are arbitrary. When is a client exactly a platinum customer (Miller in Figure 71a) and when a golden one (Brown)? What about customers who are classified sharply in the same tier, although their customer equity is quite different (Brown and Smith)? Why should iron Ford, who is as profitable as Smith, not be treated specially as Smith is? Such questions are quite difficult to answer. Using fuzzy classification, the transitions between the four tiers becomes fluent and customers can partly belong to more than one tier at the same time. Miller and Brown are both an "alloy" of platinum and gold, and also Smith and Ford are partially golden and iron at the same time. Defining only two terms ‘least profitable’ (or iron) and ‘most profitable’ (or gold) customers in Figure 71b, the customers can be classified fuzzily in the customer equity pyramid. The fuzzy classified customer equity pyramid has a more neutral and proper semantic and the customers are no longer privileged or discriminated. - 90 - Chapter 5: Fuzzy Customer Segmentation 5.2 Fuzzy Market Segmentation Just as customers, buyers of a whole market differ in their wishes, resources, locations, buying attitudes and buying practices. Through market segmentation, companies divide large, heterogeneous markets into smaller segments of buyers with different needs, characteristics or behaviour, who might require separate products or marketing mixes [Kotler et al. 2005, p. 391]. In contrast to mass marketing, where the same marketing mix is used for all consumers and no market segmentation is undertaken, segment marketing adapts the marketing mix to segments. Niche marketing, in turn, focuses on subgroups (niches) within these segments, where often is little competition. In the case of complete market segmentation, micromarketing, products and marketing programmes are tailored to the needs and wants of narrowly defined geographic, demographic, psychographic or behavioural segments. In the extreme, micromarketing becomes individual marketing that means tailoring products and marketing programmes to the needs and preferences of individual customers [Kotler et al. 2005, p. 395]. Individual marketing has also been labelled ‘markets-of-one marketing’ or ‘one-to-one marketing’ as discussed in Section 4.1.3. Figure 72a and b show the two extremes, ‘no segmentation’ (mass marketing) and ‘atomistic segmentation’ (individual marketing) of a market with six consumers. Considering three income classes (1: ‘low’, 2: ‘medium’, 3: ‘high’ in Figure 72c), the market is segmented into three segments of different sizes. Three consumers have a ‘low’ income (1), one has a ‘medium’ (2) and two have a ‘high’ income (3). In addition, the market can be segmented by the age of the consumers (Figure 72d; A: ‘young’, B: ‘old’) into two segments. The use of both criteria, income and age, divides the market into five market segments (1A, 1B, 2B, 3A and 3B in Figure 72e). a) No segmentation (mass marketing) b) Atomistic segmen- c) Segmentation of income d) Segmentation of tation (individual marketing) groups (1: ‘low’, 2: ‘medium’, 3: ‘high’ income) 1 2 e) Segmentation of age groups (A; ‘young, B: ‘old’) income and age groups B 1A B 1A A 1 3 1 3B A 3 1B B 2B A 3A Source: adapted from [Kotler and Bliemel 2001, p. 417] Figure 72: Sharp Market Segmentation Market segments can be defined in many different ways. The different market segments shown in Figure 72 are demographic segments. According to [Kotler and Keller 2005, p. 241], another way to curve up a market is to identify preference segments. Three different patterns of preferences can emerge: homogeneous, diffused or clustered preferences (compare Figure 73). - 91 - Chapter 5: Fuzzy Customer Segmentation c) b) a) a) Homogeneous preferences: market with no natural segments: all consumers have same preferences. b) Diffused preferences: consumers of this market vary greatly in their preferences, and are scattered throughout the space. c) Clustered preferences: market with three distinct preference clusters, so called natural market segments. Source: adapted from [Kotler and Keller 2005, p. 242] Figure 73: Basic Market-Preferences Patterns However, the patterns in Figure 73 are theoretical and unrealistic illustrations. There are usually no homogeneous preferences in real markets and it is also rarely the case that markets have clear, distinct and homogeneous clusters of different preferences. Real preferences mostly range somewhere in between homogeneous, diffused and clustered preferences. The sharp market segmentation in demographic segments shown in Figure 72 is also a problem. This approach assumes that it can be clearly distinguished between consumers with a ‘low’ (1), ‘medium’ (2) or ‘high’ income (3), and between ‘young’ (A) and ‘old’ (B) consumers. However, how is a ‘low’, ‘medium’ or a ‘high’ income defined and when is a consumer ‘young’ and when ‘old’? Responses to these questions are usually sharp classifications shown Figure 74: people between 0 and 39 years are ‘young’, ‘middle-aged’ are between 40 and 59, and people over 60 years are ‘old’. An income between 0 and 2499 € is defined as ‘low’, a ‘medium’ income ranges between 2500 and 4999 €, and people with a ‘high’ income earn more than 5000 €. Although Miller and Brown have nearly the same age (Miller 38 years and Brown 41) and same income (Miller: 4920 € and Brown: 5100 €), Miller is classified as ‘young’ and his income as ‘medium’, but Brown as ‘middle-aged’ and his income as ‘high’. μ young Under 40 1 ... C1) C2) Smith 70 65 60 55 C6) C4) C5) 50 45 Brown 40 35 C9) C7) C8) Miller Ford 20 0 1000 2000 under 2'500 3000 4000 5000 2’500 - 4'999 6000 40 39 C3) Smith C2) C1) C6) C5) C4) Brown C9) 20’000 over 5'000 C8) Miller C7) 0 Ford 0 2499 2500 4999 5000 low 30 25 60 59 Sharp classification medium Income (gross income per month, in €) 0 1 μ low income μ medium income μ high income Figure 74: Fuzzy Market Segmentation of Income and Age - 92 - Income C3) old 75 middleaged 40-59 years μ middle-aged Over 60 80 Age young μ old Age … Chapter 5: Fuzzy Customer Segmentation This example points out: it does not make sense to classify the age and income of a person sharply: why should a 39 year old person be labelled ‘young’, but a 40 year old one suddenly ‘middle-aged’? Why should a ‘middle-aged’ person of 59 years be classified abruptly as ‘old’ with 60? The transitions between the phases in one’s life are fluent. The membership functions in Figure 74 reflect mathematically these fluent transitions between the phases. With fuzzy classification, a person can be classified as ‘young’ and ‘middle-aged’ (respectively as ‘middle-aged’ and as ‘old’) at the same time, and the income can be categorised partially as ‘low’ and partially as ‘medium’ (respectively as ‘medium’ and as ‘high). However, not only socio-demographic market segmentation but also other types and categories of segmenting criteria could or should be classified fuzzily. According to [Kotler et al. 2005, pp. 398ff], consumer markets can be segmented by geographic, demographic, psychographic and behavioural market segmentation (see Appendix 5, p. 141): Geographic segmentation calls for dividing the market into different geographical units, such as nations, states, regions, counties, cities or neighbourhoods. Demographic segmentation consists of dividing the market into groups based on variables such as age, gender, sexual orientation, family size, family life cycle, income, occupation education, religion, ethnic community and nationality. Psychographic segmentation divides buyers into groups based on social class, lifestyle or personality characteristics. Behavioural segmentation divides buyers into groups based on their knowledge, attitudes, uses or responses to a product or service, or based on other criteria of purchase behaviour. As shown in Appendix 5, most of the market segmentation variables are adequate for fuzzy classification with discrete or continuous membership functions. Especially behavioural segmentation variables are promising to define fuzzy market segments, marketing strategies and 0 C1) Fuzzy segment 2 (fS2); Strategy B Fuzzy segment 1 (fS1); Strategy A C4) C3) Fuzzy segment 4 (fS4); Strategy D Fuzzy segment 3 (fS3); Strategy C 0 1 fS3; Strategy C fS1; Strategy A fS2; Strategy B fS5; Strategy E 1 0 0 1 μ low variable X μ high variable X μ low variable X Figure 75: Fuzzy Market Segments and Strategies - 93 - fS4; Strategy D μ high variable X Market segmentation variable X 1 C2) Market segmentation variable Y μ low variable Y μ high variable Y μ low variable Y μ high variable Y Market segmentation variable Y Market segmentation variable X marketing mixes. Figure 75 shows a general example how to define fuzzy market segments. Chapter 6 Fuzzy Credit Rating - 94 - Chapter 6: Fuzzy Credit Rating 6.1 Methods of Sharp Credit Rating 6.1.1 Definitions Another example of customer or market segmentation is the process of credit rating, which ends in a rating of the rating subject (for instance a loan applicant) in a rating or risk class. To manage the credit business profitably, a bank has to classify loan applicants according to their real creditworthiness (I 68), that means according to their default risk. It is in every bank’s concern to evaluate loan applicants and their creditworthiness as good as possible. Creditworthiness is the ability, intention and financial capability of a borrower to repay debt. Credit scoring is a quantitative approach used to measure and evaluate the creditworthiness of a loan applicant [Hofstrand 2006]. An aim of credit scoring is to determine the credit risk, that risk assumed for the possible nonpayment of credit extended. In Anglo-Saxon literature on credit scoring, often the C’s of credit are mentioned, e.g. Character, Capital, Capacity, Collateral and Condition. In german literature, a distinction is often made between personal and material creditworthiness. A borrower is considered as personally creditworthy, if he deserves confidence due to its reliability, professional qualification and its business acumen. Material creditworthiness is supposed, if the current or expected economical circumstances of the borrower guarantee the payment of interests and the repayment of the loan. The following sections discuss the internal rating of banks. Considering conventional methods of credit rating, subjective expertise is compared to statistical methods. 6.1.2 Subjective Expertise Subjective heuristics, expertise, checklists and systematic scoring models are widely used methods of credit rating in banking practice. They contain a number of criteria about the creditworthiness of a commercial or private borrower. In retail banking, following information about the personal creditworthiness of a loan applicant for a consumer loan are examined: age, civil and family status; number and age of the children profession and qualification employer, job circumstances and duration of employment recovery of claims and garnishment reason for credit. Considering the material creditworthiness, following information is evaluated: monthly net income, additional incomes and security of income property - 95 - Chapter 6: Fuzzy Credit Rating loan securities account information at the internal or external bank alimonies rent or mortgage rate leasing rates, other financial obligations and dept service. Credit agreements often contain the following basic points: amount of credit, interest rate, repayment conditions, credit period (duration of the credit) and loan securities. 6.1.3 Statistical Methods In contrast to heuristic scoring, empirical or statistical credit scoring eliminates the subjectiveness of loan officers. Statistical methods divide borrowers into two classes: customers are either ‘not creditworthy’ or ‘creditworthy’. The membership to one of the classes depends on a score based on a criteria catalogue, using a discriminant function. Important statistical methods for credit rating are, for instance: multivariate discriminant analysis, logit analysis and artificial neuronal network. The multivariate discriminant analysis measures the dependence between different metric variables (e.g. income) and a nominal grouping variable (‘not creditworthy’ or ‘creditworthy’). In doing so, the following discriminant function f(z)i f (z )i = b0 + b1 ⋅ x1i + b2 ⋅ x2i + ... + bK ⋅ xKi is estimated that way, that the critical dividing value z* separates optimally the ‘creditworthy’ customers from the ‘not creditworthy’ ones (see Figure 76). It is a challenge to estimate the coefficients (bK) of the discriminant function that the type I and II errors (α- and β-errors) are as small as possible. Group 0 (not creditworthy) znot creditworthy Group 1 (creditworthy) z* Centroid not creditworthy zcreditworthy f(z) Centroid creditworthy Type I Error (β-error): Type II Error (α-error): A loan applicant receives no credit, although he is creditworthy (/solvent) A loan applicant receives a credit, although he is not creditworthy (/solvent) Dividing value = critical discriminant value Figure 76: Discriminant Function and Type I and II Errors - 96 - Chapter 6: Fuzzy Credit Rating The error terms are low, if the centroids z of group 0 and 1 are far away from each other, and if the variance within each group is very small (for details see [Backhaus et al. 2006]). In contrast to discriminant analyses, logit analyses or loglinear models consider non-metric, qualitative variables. They are suited for the analysis of the dependence of several non-metric independent variables and a nominal grouping variable. Artificial Neural Networks (ANN) try to reduce type I and II errors by linking logistic, nonlinear functions. A neuronal network can be defined as “a collection of neuron-like processing units with weighted connections between the units” [Han and Kamber 2006, p. 24]. All neurons, linked to an ANN, receive, process and relay signals. The architecture of a neural network consists of three layers shown in Figure 77. not creditworthy creditworthy Output data: credit applicant is not creditworthy or creditworthy Output layer Hidden layer Neural network Input layer c1 c2 Input data: creditworthiness criteria ci of a credit applicant c4 C3 Figure 77: Architecture of a Neural Network for Credit Rating The input layer receives signals of the criteria ci. Neurons of the hidden layer are weighting and processing each signal received from an input layer and relay them to another hidden or to the output layer. The weights of the connections, which are adapted during the learning process, play an important rule, since they represent the experienced knowledge. With increasing training, the non-linear discriminant function fits optimally to the data set in Figure 78. c2 c2 Separation with artificial neural network Separation with discriminant function Artificial neural networks achieve good classification results and they often have a higher hit quote than the discriminant analysis Further reading about credit rating with artificial neural network see for instance: [Krause 1992, Füser 2001, Kilb 2002] c1 z* Not creditworthy c1 creditworthy f(z) Source: adapted from [Kilb 2002, p. 51] Figure 78: Discriminant Functions in Discriminant Analysis and ANN - 97 - Chapter 6: Fuzzy Credit Rating 6.1.4 Disadvantages of Sharp Credit Rating All considered methods of credit rating have certain advantages, and also disadvantages: Heuristics and checklists are subjective and it is often discretionary to bring contradictory statements together. Different credit experts mostly evaluate and weight the same credit with identical facts quite different. The disadvantage of the multivariate discriminant analysis is that only metric criteria can be taken into account. According to [Kilb 2002], the quote of misclassifications of the discriminant analysis in retail banking is relatively high. Logit analyses or logistic regression analyses have the drawback that non-linear correla- tions are difficult to model. Time invariance and representativeness of the models and the data often is not guaranteed. The crucial weakness of artificial neural networks is that the processes, results and the relations between in- and output data are not transparent for the normal user. The hidden layer of neuronal networks is a black box. As a result, artificial neural network are rarely used for credit rating in business practice. Statistical methods in general do not consider specific and individual circumstances and particularities. As a result, statistical methods are often combined with subjective expertise to hybrid methods in credit rating practice,. Another disadvantage of subjective expertise and statistical methods of credit rating is that they usually result in sharp classifications of loan applicants. The material or personal creditworthiness, or other criteria for creditworthiness of loan applicants often are rated sharply as ‘worthy’ or as ‘not worthy’. In critical or border cases, if a credit applicant is rated near the cut-off-score (the dividing value which separates the creditworthy borrowers from the rest), sharp credit rating may lead to incorrect and wrong decisions, to misclassifications as the type I and II errors are. Only a little variation of one of the rating criteria may result in another decision concerning the loan application. In addition, the sharp rating of very different risks often results in the same overall credit rating of a loan applicant. One the other hand, applicants with the same values of the attributes can be aggregated to a different overall rating. - 98 - Chapter 6: Fuzzy Credit Rating 6.2 Methods of Fuzzy Credit Rating 6.2.1 Existing Literature on Fuzzy Credit Rating Whether a loan applicant is creditworthy or not, is not a question that can be answered easily with "yes or no", but rather with "more or less". It is in the nature of credit rating that information and data are inconstant, incomplete, imprecise and fuzzy. The first authors who recognised this and associated credit rating with fuzzy classification were Hans-Jürgen Zimmermann and Peter Zysno [Zimmermann and Zysno 1982, 1983, Zimmermann 1993, 1997, Zysno 1980]. They classified hierarchically the category ‘creditworthiness’ into a four-level pyramid with different sub-categories (see Figure 79). Creditworthiness (γ = 0.59) Personal creditworthiness (δ = 0.95) Material creditworthiness (δ = 1.05) (γ = 0.55) Loan securities (δ = 0.71) (γ = 0.99) Other net property (δ = 0.61) (δ = 0.81) (γ = 0.58) Income minus expenses (δ = 1.53) (γ = 0.92) Continuity of margin (δ = 1.26) (γ = 0.60) Potential (δ = 0.93) Liquidity (δ = 1.39) (γ = 0.90) Property minus long term debts (γ = 0.78) (γ = 0.55) Physical & mental potential (δ = 1.06) Business behaviour (δ = 0.97) (γ = 0.76) (γ = 0.55) Motivation Economic thinking (δ = 0.80) (δ = 1.01) Conformity social & economic standards (δ = 0.93) Source: adapted from [Zimmermann 1993, p. 366] Figure 79: Hierarchy of Creditworthiness with Weights δ and Parameters γ The fuzzy set ‘creditworthiness’ is defined as a composition of the other fuzzy sets. The model by Zimmermann and Zysno includes remarkable findings. By testing empirically the discussed compensatory operators γ and the weights δ, the prediction results of the creditworthiness of test loan applicants with fuzzy classification were significantly better than with sharp classification [Zimmermann and Zysno 1982]. In the last years other reviews about fuzzy credit rating were published. [Romaniuk and Hall 1992] developed an expert system (FUZZNET) by using a fuzzy connectionist model. Similarly, [Levy et al. 1991] programmed a system to evaluate a company’s financial position. [Hofmann et al. 2002] tested empirically different fuzzy approaches, genetic fuzzy classifiers and neuro fuzzy algorithm. Their conclusion: fuzzy classifiers achieve better credit rating results than neuro fuzzy or conventional, sharp algorithms like C4.5. [Chen and Chiou 1999] chose a similar approach as this thesis does. In their model they define fuzzy sets, membership functions, membership degrees to five rating levels (A to E), linguistic variables and a fuzzy integral (i.e. an evidence fusion technique). - 99 - Chapter 6: Fuzzy Credit Rating The model was applied to a credit rating system in Taiwan, operated for small and medium enterprises. The evaluation criteria of this credit rating system were modelled as the hierarchical decision structure shown in Figure 80. Liquidity ratios (g11 = 0.60) Financial structure ratios (g12 = 0.60) Financial conditions 1 (g = 0.68) Profitablitity ratios 13 (g = 0.52) Efficiency ratios (g14 = 0.45) Quick ratio Current ratio Debt ratio Long-term asset efficieny ratio Interest expense to net sales Profit margin before tax Return on net worth before tax Inventory turnover Receivable turnover Total assets turnover Administrations personal credit (g21 = 0.23) Administrations experiences (g22 = 0.16) Overall credit level General Management (g2 = 0.55) Stockholders’ structure type (g23 = 0.11) Ø sale growth rate last three years (g24 = 0.16) Condition of capital increment (g25 = 0.10) Outstanding check records (g26 = 0.24) Characters & Perspectives (g3 = 0.44) Equipment & technologies (g31 = 0.24) Product marketability (g32 = 0.31) Collateral (g33 = 0.20) Conditions of industry next y. (g34 = 0.25) Source: [Chen and Chiou 1999, pp. 408ff] Figure 80: Credit Rating Hierarchy with the Degree of Importance gi of each Criterion [Chen and Chiou 1999] proved that with the fuzzy approach the overall credit rating is more sensitive to changes of credit information, especially to small changes of a single criterion. “Moreover, the description of the final credit-rating results in terms of the membership degrees of the five rating levels can provide loan officers with more valuable information in decision making” [Chen and Chiou 1999, p. 416]. As a result, credit management or contractual terms and conditions, like the amount of credit, credit period or the interest rate, can be better adapted and aligned to the exact credit information and the default risk of a borrower. The next section will discuss another fuzzy credit rating approach using the fuzzy Classification Query Language (fCQL) and a credit rating hierarchy for the bank’s internal credit rating of private borrowers. - 100 - Chapter 6: Fuzzy Credit Rating 6.2.2 Fuzzy Credit Rating with fCQL The discussed sharp and fuzzy methods of credit rating so far, can be classified in Figure 81. According to [Füser 2001], fuzzy logic can be categorised as a method of Artificial Intelligence (AI), beside Artificial Neural Networks (ANN), expert systems, and others. Conventional methods Methods of Artifical Intelligence (AI) Fuzzy credit rating Statistical methods Subjective methods Sharp credit rating adaptive, non-linear fuzzy information processing Subjective expertise & checklists Scoring models (point rating systems) Univariat analysis (traditional financial analysis) Multiple discriminant analysis Logit models Theories of evolution Artificial neuronal networks Genetic algorithms Fuzzy logic Neuro fuzzy models Fuzzy classification NFE System Fuzzy Neuronal expert expert system systems Fractal Expert Chaos geometry systems theory Synergetic static, if-whenrules fuzzy database queries fCQL toolkit fCQL Relational database system SQL Source: adapted from [Füser 2001, p. 270] Figure 81: fCQL as a Method of Artificial Intelligence As discussed in the second chapter, with fuzzy logic, vague or imprecise linguistic variables of human thinking and colloquial language can be mathematically reproduced and they become formally accessible for computers and for an information or expert system. The approach of fuzzy classification and fCQL allows to work with continuous and discrete variables and the definition of colloquial terms of credit rating, like ‘definitely creditworthy’, ‘rather creditworthy’ or ‘insufficient creditworthy’. Considering continuous variables, even more precise statements can be made: for example ‘30% moderately creditworthy’, ‘60% creditworthy’, ’80% rather creditworthy’, and so on. However, the approach of fuzzy classification and fCQL is to be distinguished from artificial neuronal networks, expert systems and from other methods of AI (in Figure 81). Based on an example of credit rating practice, a hierarchy of creditworthiness will now be discussed. It is assumed that the ‘overall creditworthiness’ of a loan applicant on the top level (L1 in Figure 82) of the hierarchy of creditworthiness is defined by ‘personal creditworthiness’ and ‘material creditworthiness’ on the second level (L2). On the third level (L3), personal creditworthiness includes the ‘family situation’ and ‘employment’, on the one hand. On the other hand, material creditworthiness contains the ‘income’ and ‘outgoings’. These four aggregations are defined by a number of different criteria of credit rating on the fourth level (L4). They are usually asked for in an application form for a private credit and analysed by the bank. - 101 - Chapter 6: Fuzzy Credit Rating L1: Overall creditworthiness Personal creditworthiness L2: Family situation L3: Outgoings Income Employment Age Civil status Family status Living conditions Number/age of children etc. L4: Material creditworthiness Net income Security of income Property Loan securities Account information etc. Profession Qualification Employer Duration of employment etc. Rent or mortgage rate Alimonies Financial obligations Leasing rates Reason for credit etc. Figure 82: Practice-Related Example of a Hierarchy of Creditworthiness Regarding the income, for instance, the loan applicant has to answer his income level, additional income, property, loan securities (e.g. surety, guarantee, lien and mortgage), account information by the internal or external bank, and other criteria. Following a bottom-up approach of fuzzy credit scoring, all predefined, and weighted scores of all the criteria on the bottom level L4 are evaluated by bipolar rating scales. Qualitative attributes or criteria of credit rating are assigned to discrete domains and member- ship functions. Figure 83a shows an example of a discrete, six-level rating scale to determine and rate the attribute ‘loan securities’. The other example, Figure 83b, represents a continuous scale with continuous membership functions of the quantitative attribute ‘income’. To each value of the membership functions a number of scores is assigned. a) b) Loan securities insufficient very low 0 low sufficient low rather low rather high high very high 2 4 6 6 8 Equivalence class 10 0 0.2 0.4 0.6 0.8 1 [0, ... , 3'499] Equivalence class high Terms 3499 3500 ≥10'000 0.1 scores per 0.01 value of μ high e.g.: 0.56 = 5.6 scores 0 [very low, low, rather low] [rather high, high, very high] Linguistic variable (Attribute) Income Equivalence class [3'500, ... , 10'000] Equivalence class Domain Scale Score Context 0 Membership functions 0.44 0.56 μ insufficient μ sufficient 1 μ low μ high Figure 83: Examples of a Qualitative and a Quantitative Attribute of Fuzzy Credit Scoring The evaluated score S(Aijkl) of all rating scales of the different attributes (Aijkl) considered in L4 are accumulated with following scoring function. The scores on the fourth level (L4) define the scores on the third level (L3), ‘family situation’ S(A311), ‘employment’ S(A312), ‘income’ S(A321), and ‘outgoings’ S(A322). - 102 - Chapter 6: Fuzzy Credit Rating n= 5 n= 5 n= 5 n= 5 l =1 l =1 l =1 l =1 S(A ijkl ) = ∑ S(A 411l ) + ∑ S(A 412l ) + ∑ S(A 421l ) + ∑ S(A 422l ) L4: L3: Family situation Employment Income Outgoings S(A311) S(A312) S(A321) S(A322) Personal creditworthiness S(A21) L2: L1: (Scoring function) Material creditworthiness S(A22) Overall creditworthiness S(A1) The scores on the third level L3 define the scores of the second level (L2) and first level (L1) of the hierarchy, that means the personal (S(A21)) and material (S(A22)) and the overall creditworthiness (S(A1)). Appendix 6 (see p. 142) shows formal details, i.e. all attributes, levels, classes, terms and domains of the scoring function and the hierarchy of creditworthiness. This example of hierarchical fuzzy credit scoring can also be shown in a matrix: the left side of Figure 84 shows a fuzzy classification of the ‘overall creditworthiness’, the right side the fuzzy classification of ‘material creditworthiness’ and, at the bottom, the ‘personal creditworthiness’. The membership degrees of the classified loan applicants Ford, Smith, Brown and Miller can be calculated on the different levels Li of the hierarchy of creditworthiness. This hierarchical fuzzy credit classification approach has the advantage that the degree of creditworthiness can be queried on the different levels of the hierarchy. If the rating of one or several levels of the creditworthiness of a bank customer degrades, a trigger mechanism warns the manager. In addition, possible developments of a customer’s creditworthiness can be simulated with different scenarios (e.g. worst, realistic or best case). Income (Score) Ford 0 0 0 Interest rate: iC3 = 14% 18.5% creditworthy 24.8% pers. not creditworthy 24.8% mat. not creditworthy 31.9% not creditworthy 100% not creditworthy 49 50 100 1 0.44 0.6 0.56 μ pers. not creditworthy 0 24 25 μ pers. creditworthy Miller C1-2) C1-1) Employment Personally not creditcreditworthy worthy Brown Smith C1-3) Family situation not creditworthy 0 24 25 Figure 84: Hierarchical Fuzzy Classification of Creditworthiness - 103 - Smith 50 Family situation (Score) C1-4) Personally not Ford creditworthy 0 0.4 0 50 Employment (Score) no credit (interest rate: iC4 = 18%) C3) Materially not creditworthy; 50 Smith C4) Not creditworthy; 24 25 49 0.4 Brown 0 1 0.6 0.28 Personal creditworthiness (Score) 0.72 Brown C2-4) C2-3) Materially Income not Ford not credit- creditworthy worthy Outgoings (Score) 50 100% creditworthy 34.8% creditworthy 30.2% pers. not creditworthy 19.1% mat. not creditworthy 15.9% not creditworthy 50 Miller C2-2) C2-1) Outgoings not Materially creditworthy creditworthy 24 25 100 C2) Personally not C1) Creditworthy Miller creditworthy Interest rate: iC1 = 6% Interest rate: iC2 = 10% μ mat. not creditworthy μ mat. creditworthy Material creditworthiness (Score) Chapter 6: Fuzzy Credit Rating In addition, fuzzy classification or credit scoring enables the calculation of individual interest rates, i.e. of individual risk premiums. To each class of the fuzzy classification in Figure 84 an interest rate is assigned; for example: C1: 6%, C2: 10%, C3: 14% and C4: 18%. The premium is to reflect the risk class as accurate as possible. According to their degree of creditworthiness, for each of the loan applicant an individual interest rate can be calculated: Interest rate iFord = 1·18 = 18%. Interest rate iSmith = 0.185·6 + 0.248·10 + 0.248·14 + 0.319·18 = 12.8% Interest rate iBrown = 0.348·6 + 0.302·10 + 0.191·14 + 0.159·18 = 10.6% Interest rate iMiller = 1·6 = 6% Classified sharply, Smith belongs entirely to C4 and has to pay a very high risk premium of 18%, like Ford, although Smith is nearly in the same position as Brown who is classified in C1 and enjoys good conditions: he has to pay an interest rate of 6% only. Although Miller is much more creditworthy than Brown, he is also classified in C1 and pays the same interests of 6%. With a fuzzy calculated interest rate, customer Smith is not disadvantaged any longer in comparison to Brown, but still has to pay quite high interests (of 12.8%). Brown is no longer privileged and has to pay 10.6%. Miller still has to pay 6% only. Fuzzy classification enables a fair and non-discriminatory calculation of risk premiums for loan applicants or bank customers, according to their creditworthiness or default risk. However, in the case of the fuzzy credit rating, the bank manager or the loan officer still is confronted with the problem he may not allow a credit beyond a certain limit of default risk or lack of creditworthiness. This limit (cut-off-score) can be fixed at a certain level of the interest rate (e.g. no higher interest rates than 15%). Alternatively, the credit is refused, if the fuzzy calculated membership degree of a classified loan applicant to C1 decreases, for instance, under 10%, or if the membership degree to C2, C3 or to C4 increases over 50%. Depending on the requirements of bank, or on the knowledge of the loan officer, or depending on the situation, the credit rating can be more or less strictly. According to [Gachet 2006], not only individual interest rates can be calculated with fuzzy classification, but also an individual credit period. Going one step further, the individual interest rate could be calculated based on the attribute ‘creditworthiness’ (with the terms ‘sufficient’ or ‘excellent’), ‘credit period’ (‘short-term’ and ‘long-term’) and on the attribute ‘amount of credit’ (‘small credit’ or ‘large credit’). Figure 85 shows such a three-dimensional fuzzy classification in credit rating. To each of the classes an interest rate is assigned under following realistic assumptions: the nominal interest rate is lower for long-term credits than for short-term credits large credits than for small credits and for clients with an excellent creditworthiness than for clients with a sufficient creditworthiness. - 104 - Chapter 6: Fuzzy Credit Rating a) b) C5) 100% Creditworthiness Creditworthiness (Score) (Score) Excellent Credit period (months) Smith 100 99 100 99 60 Short-term 12 50 Small credit 19 20 Large credit Brown, Miller Smith C5) 100% C3) 100% 100 μ sufficient Sufficient Long-term 36 35 3 200 μ excellent 200 Amount of credit (thousand €) 1 0 Ford 55 3 0 1 C4) 100% C1) 12.8% C2) 9.6% C3) 11.2% C4) 8.3% C5) 17.5% C6) 13.4% C7) 15.4% Brown C8) 11.7% C1) 14.9% Smith C2) 13.1% C3) 17.3% C4) 15.2% C5) 9.7% C6) 8.4% C7) 11.5% C8) 9.9% C3) 42.9% Ford C4) 57.1% Müller Credit period (months) 60 μ long-term 36 35 12 100 Amount 19 20 μ short-term of credit (in thousand €) μ small credit μ large credit Figure 85: Thee-Dimensional Sharp (a) and Fuzzy (b) Credit Rating The attributes, equivalence classes [in squared brackets] and the terms (in round brackets) of the eight classes C1 to C8 in Figure 85a) and the different interest rates are shown in Table 16. Table 16: Interest Rates for Different Loan Categories Class C1 C2 C3 C4 C5 C6 C7 C8 Creditworthiness [Score] [100, 200] [100, 200] [50, 99] [50, 99] [100, 200] [100, 200] [50, 99] [50, 99] Attributes, [equivalence classes] and (terms) Amount of credit (Term) Excellent Excellent Sufficient Sufficient Excellent Excellent Sufficient Sufficient [Euros] [20'000, 100'000] [3000, 19’000] [20'000, 100'000] [3000, 19’000] [20'000, 100'000] [3000,19’000] [20'000, 100'000] [3000, 19’000] (Term) Large credit Small credit Large credit Small credit Large credit Small credit Large credit Small credit Credit period [Months] [12, 35] [12, 35 ] [12, 35] [12, 35] [36, 60] [36, 60] [36, 60] [36, 60] (Term) Short-term Short-term Short-term Short-term Long-term Long-term Long-term Long-term Interest rate 8% 10% 12% 14% 5% 7% 8% 9% If the customers from the example above were applying for a credit, they are sharply classified to the classes of the following Table 17: Table 17: Sharp Classification of the Loan Applicants Loan applicant Class Smith Ford Brown Miller C3 C4 C5 C5 Attributes, [values of the loan applicants] and (terms) Creditworthiness Amount of credit Credit period [Score] 97 10 109 189 (Term) Sufficient Sufficient Excellent Excellent [Euros] 24'000 16'000 30'000 90'000 (Term) Large credit Small credit Large credit Large credit [Months] 32 18 38 54 (Term) Short-term Short-term Long-term Long-term Interest rate 12% 14% 5% 5% Although Smith and Brown have similar values (their score of creditworthiness: 97, 109; their amount of credit: 24'000, 30'000 €; their credit period: 32, 38 months), they are classified in different classes with different interest rates. Smith (12%) has to pay a 2.4 times higher interest rate than Brown (5%). Miller, with 80 scores more, a three times higher amount of credit and a contract which is two years longer than Browns, has to pay the same 5%. - 105 - Chapter 6: Fuzzy Credit Rating With the fuzzy classification approach (compare Figure 85b), such discrepancies are eliminated and a exact, individual interest rate can be calculated, according to the values of the attributes ‘creditworthiness’, ‘credit period’ and to ‘amount of credit’ of a loan applicant: Interest rate iFord = 0.429·12 + 0.571·14 = 13.14% Interest rate iSmith = 0.149·8 + 0.131·10 + 0.173·12 + 0.152·14 + 0.097·5 + 0.084·7 + 0.115·8 + 0.099·9 = 9.59% Interest rate iBrown = 0.128·8 + 0.096·10 + 0.112·12 + 0.083·14 + 0.175·5 + 0.134·7 + 0.154·8 + 0.117·9 = 8.59% Interest rate iMiller = 1·5 = 5% Classified fuzzily, Smith is to pay a lower interest rate of 9.59% than in a sharp classification (12%). Ford is also to pay a slightly lower rate of 13.14% (sharp: 14%). In contrast, Brown has to pay a higher rate of 8.59% (sharp: 5%). For Miller the interest rate (5%) remains the same. 6.2.3 Other Applications for Fuzzy Classification in Banking Considering other important criteria of bank customer in private banking, e.g. a customer’s assets, capital, turnover, profit, lifetime value or his cross-selling potential, fuzzy classification is interesting for offering offer individualised and personalised services or bank products. Such mass customisation, based on the fuzzy classification approach, leads to added-value for the customer, may to higher customer retention (i.e. profits) and to competitive advantages for the bank. Other banking sectors, e.g. the credit rating of companies, are also promising for fuzzy classification. The credit rating of companies or business customers is much more complex than the rating of private customers, since the evaluation deals with many different rating criteria and standards. In this case, the application of fuzzy classification is even more pertinent than the credit rating of private loan applicants discussed in this chapter. - 106 - Chapter 7 Conclusion - 107 - Chapter 7: Conclusion 7.1 Summary Conventional data analysis methods in statistics and data mining have certain disadvantages: classified elements are mostly assigned sharply to one single class. Such sharp classifications can be arbitrary, problematic, incorrect and unfair, as many examples of the master thesis explained: although elements had nearly the same values, they were classified in different classes. In contrast, elements with very different values can be classified in the same class. In business practice, such misclassifications and discrepancies may have negative effects, for instance, if a key account is managed in the same way as an unprofitable customer, or if two similar customers notice that they are treated differently by the company. With fuzzy classification, these problems do not occur. Fuzzy classification and fCQL (fuzzy Classification Query Language) combine fuzzy logic and relational databases and allow the classification of customers, or any other elements, into more than one class at the same time. Defining attributes, terms and fuzzy sets, which are determined by membership functions over the whole domain of an attribute, the classification space becomes fuzzy. That means that the classes sharp borders disappear and there are continuous transitions between the classes. The fuzzy approach with fCQL has further advantages: it enables the reduction of complexity without loss of information, the use of numerical (quantitative) and non-numerical (qualitative) values, a clear semantic and a human-oriented query process with linguistic variables and terms. In addition, dynamic and multidimensional fuzzy classifications can be undertaken. This thesis has basic questions and answers. Following basic findings can be summarised: ‘Where’ can fuzzy classification be used in business management? It could be used, for instance, in different fields of marketing (¨Table 18; ¨RQ1) and of Customer Relationship Management (CRM; ¨Table 20; ¨RQ3) ‘How’ could fuzzy classification be applied? Combined with management tools, fuzzy classification can be applied as fuzzy portfolio analysis, fuzzy SWOT analysis, fuzzy ABC analysis and as fuzzy scoring method (¨Table 19; ¨RQ2). ‘What for’ can fuzzy classification be used? It is especially suited for Customer Performance Measurement (CPM; ¨Table 21 ¨RQ4), using relevant Customer Performance Indicators (CPI; ¨Table 22; ¨RQ5). Since the classification of the indicators is a precondition for the analysis, evaluation and segmentation of customers (¨Table 23; ¨RQ6), fuzzy classification is a crucial task of customer performance measurement. In addition, fuzzy customer segmentation can be used for credit rating (¨Table 24; ¨RQ7). ‘Why’ should fuzzy classification be used? In contrast to sharp methods, fuzzy classification avoids misclassifications, enables a more precise classification and management of customers according to their values, an improved exploitation of customer potential and a better allocation of limited ressources for effective and efficient CRM. - 108 - Chapter 7: Conclusion Table 18: Results of Research Question (RQ) 1 What are potential fields and topics for business applications for fuzzy classification in general? Fuzzy classification (fc) supports generally the management functions analysis and control; for instance, the analysing and controlling of performance indicators in CRM and marketing. As summarised above, fc is suited for Customer Relationship Management (CRM; ¨Section 4.1; ¨RQ 2), Customer Performance Measurement (CPM; ¨Section 4.2; ¨RQ 3), fuzzy customer 1 segmentation (¨Section 5.1; ¨RQ 4) and for fuzzy credit rating (¨Section 6.2; ¨RQ 6). Data of market research can be used for fuzzy market segmentation (¨Section 5.2). Fuzzy classification can be applied to widely used management tools and methods (¨RQ 5), as fuzzy portfolio analysis (¨Section 3.2), fuzzy SWOT analysis (¨Section 3.3; fuzzy Strength, Weakness, Opportunity and Threat/risk matrix), fuzzy ABC analysis (¨Section 3.4), fuzzy scoring methods or fuzzy RFM method (¨Section 3.5) and as fuzzy cost-benefit analysis. Empirical research confirms that CRM, customer segmentation and performance management became very important in business practice. These concepts are also most suited for the application of fuzzy classification, as discussed in Chapters 4 and 5, and shown in Figure 86. However, the most promising topic for the application of fuzzy classification is customer portfolio analysis, which is easy to understand and implement, and widely used in practice. According to a study of [Krafft 2007], 44% of all firms use customer portfolios analysis. 32% of the firms analyse customer portfolios regularly, 48% sporadically [Reinecke and Herzog 2006]. Importance in business practice ... Business process reengineering Total quality management ... Benchmarking Strategic planning Mission and vision statement Core competences Promising topics Supply chain management SWOTanalysis ... Discriminant analyse ... Regression analysis Mass marketing Transaction marketing ... Correlation analysis Value chain ... Conjointanalysis Association analysis Analysis of variance Logitanalysis Cost-benefit analysis Five-forcemodel ABCanalysis Customer segmentation Performance measurement Balanced scorecard Scoringmodels Market segmentation ... Relationship marketing Decision Individual marketing trees One-to-one marketing Mikromarketing Multidimensional scaling ... Fuzzy classification management tool Fuzzy statistical or data mining method Sharp or fuzzy application possible Fuzzy application to marketing concept or field Portfolio analysis CRM Credit rating Customised marketing Cluster analysis Personalisation Mass customisation Customer profiling Artificial neural network Suitability for fuzzy application Management tool Statistical or data mining method Marketing concept or field Conventional or sharp approach Figure 86: Promising Management Tools, Methods and Concepts for Fuzzy Classification - 109 - Chapter 7: Conclusion C1) Development customers Star customers (question marks) (stars) Brown C3) Smith C4) Renunciation customers 100% (poor dogs) renunciation 14% C1) 1 0 Ford 0 21% C2) 26% C3) 39% C4) 1 μ weak Absorption customers Miller 100% C1) star customer Smith Brown Miller (cash cows) 35% C1) star 24% C2) development 25% C3) absorption 16% C4) renunciation customer μ strong Cumulative share of customers C2) Competitive position μ unattractive b) Cumulative turnover Customer attractiveness μ attractive a) A-customers B-customers C-customers 0 1 0 μA μB μC 1 Figure 87: Fuzzy Classified Customer Portfolio (a) and Fuzzy ABC Analysis (b) Conventional portfolio analysis is applied in such a way that sharp classes are defined, which means that classified elements belong to one single class only. For instance, a customer is classified as a ‘star’ (Brown in Figure 87a) or as ‘renunciation customer’ (Smith). The problem: Brown and Smith are classified in different classes, although they have a similar values of the attributes. With fuzzy classification, the different values of customers are taken exactly into account: Brown and Smith belong partly to all four classes of the portfolio at the same time. Besides portfolio analysis, the ABC analysis is used by the majority of companies to segment customers, products or other objects. Surprisingly, the ABC analysis has also been applied in a sharp manner so far, although it is problematic to distinguish sharply between A-, B- and Ccustomers (Figure 87b). Classified sharply, Miller is an A-, and Brown a B-customer, although they have both nearly the same turnover. If a customer (Brown) had little higher turnover, may be only a few euros, he would slide into class A and might be managed differently as a key account. In contrast, customers with different turnover can be classified in the same class of a sharp ABC analysis: Smith is classified as a B-customer although his turnover is much lower than Brown’s. In a fuzzy ABC analysis, the transitions between A-, B- and C-customers become fluent and the customers can be precisely classified according to their real turnover. Fuzzily, Brown and Miller are partly A- and B-customers; Smith belongs partially to B and C. After the discussion of different fuzzy classification management tools (compare Table 19), CRM and possible fields, tasks or processes for fuzzy classification (see Table 20), Customer Performance Measurement (CPM) turns out to be an important task of analytical CRM. CPM is defined here as the acquisition, analysis and the evaluation of performance-related customer information, using Customer Performance Indicators (CPIs), i.e. customer-related monetary or non-monetary criteria (measures, metrics, indices, figures or ratios) about customer performance. Since it is a problem to classify and evaluate customer performance sharply, a fuzzy classification of all indicators in CPM is suggested. - 110 - Chapter 7: Conclusion Table 19: Results of Research Question 2 What are potential management tools and methods for fuzzy classification? (¨Chapter 3) Fuzzy portfolio analysis (¨Section 3.2) facilitates the classification and management of customers, businesses, Strategic Business Units (SBUs) or Fields (SBFs). Further advantages are: - dynamic analysis and monitoring of a portfolio and implementation of a trigger mechanism - fuzzy investments proportionally to the membership degrees of business units to each class - balancing of portfolio (of cash flow producing and requiring business units) by defining a balance indicator and the implementation of an trigger mechanism, which warns if the portfolio is not balanced (portfolio with insufficient actual cash flow or future potential or both) - improved management of businesses and better allocation of limited ressources. Fuzzy SWOT analysis (Strengths, Weaknesses, Opportunities, Threats) (¨Section 3.3): 2 - fuzzy strength matrix: fuzzy classification of strategic strengths (competitive advantages) - fuzzy weakness matrix: classification of primary weaknesses (competitive disadvantages) - fuzzy opportunity matrix: fuzzy classification of high opportunities (for investments) and - fuzzy threat/risk matrix: fuzzy classification of major threats/extreme risks (risk management). Fuzzy ABC analysis (¨Section 3.4): fluent transitions between A-, B- and C-customers allow a fair segmentation of customers according to their real turnover (or according to other indicators). Combination of fuzzy portfolio and ABC analysis and definition of different customer strategies. Fuzzy scoring methods (¨Section 3.5): discussion of a sharp Recency Frequency Monetary value method (problem: 20% higher score of Miller despite same purchase behaviour as Brown) - development of an improved fuzzy RFM method and the fuzzy RFM scoring of customers - fuzzy calculation of RFM incentives and personalised accounts. Table 20: Results of Research Question 3 What are potential fields, processes & instruments for fuzzy classification in CRM? (¨Section 4.1) Promising fields and concepts for the use of fc marketing and customer management are: customer acquisition and retention; individual or one-to-one marketing; micromarketing; key account management ; mass customisation; personalisation; customer profiling. The possible use of fc in customer-oriented tasks and processes of CRM: customer specific 3 information or advertising; personalised campaigns, loyalty or recovery programs; customisation of products; fuzzy calculation of individual prices, accounts, incentives, paying conditions or warranties; customer specific services and customer care according to their value to the company. Definition of a "small CRM success chain" (from customer orientation to shareholder value). Conclusion: the most promising fields for fuzzy classification in CRM: analytical CRM (aCRM) and Customer Performance Measurement (¨Section 4.2; ¨RQ 4). According to Table 21, CRM and CPM require a comprehensive number of customer performance indicators to manage and maximise customers as an asset. This work collected, defined, operationalised and discussed 170+ Customer Performance Indicators (CPIs; see Table 22, Appendix 4, pp. 136ff), which can be measured on an individual and on an aggregated level. - 111 - Chapter 7: Conclusion Table 21: Results of Research Question 4 What are the benefits of fuzzy classification in customer performance measurement? (¨Section 4.2) Fuzzy classification enables fair and exact Customer Performance Measurement (CPM). CPM is a precondition to manage and maximise customer as an asset of the company. Different dimensions and characteristics can be taken into account for CPM and fuzzy classification: unit (monetary/non-monetary), format (quantitative/qualitative), planning 4 interval (short-/long-term), time (ex-post/ex-ante), alignment (internal/external), incentives (variation/improvement), CRM layer (operational/strategic) and aggregation level (low/high). Consideration of empirical studies of customer performance measurement in business practice. Conclusion: an adequate number of Customer Performance Indicators (CPIs) is required to manage customer best possible (¨Section 4.3; ¨RQ 5). Table 22: Results of Research Question 5 What are important customer performance indicators for CPM? (¨Section 4.3) 170+ Customer Performance Indicators (CPIs) were defined, discussed and operationalised (¨Appendix 4, pp. 136ff). Description of different functions of CPIs and requirements for indicators. Discussion of six different categories of indicators: 1) Customer Performance Indicators of Revenue and Profitability (CPIP), such as customer turnover, contribution margins I-IV, gross/net profit, customer equity or customer lifetime value 5 2) Customer Investment Indicators (CII): customer costs of acquisition, retention and recovery; transaction, service, communication, contact, marketing and total customer costs; return on’s 3) Customer Relationship Indicators (CRI), e.g. customer value, satisfaction, loyalty or retention 4) Customer Recommendation Indicators (CReI), e.g. number/intensity of recommendations 5) Customer Information Indicators (Cinfl), e.g. number/quality of suggestions or complaints 6) Customer Cooperation Indicators (CCI), e.g. intention to or expertise for cooperation. Classification of the 170+ CPIs into a "big CRM success chain" (¨Figure 42; p. 60). Fuzzy classification and fuzzy Classification Management Tools (fCMT), like the fuzzy portfolio analysis or ABC analysis and scoring methods, are general instruments to analyse and classify customer performance indicators. In addition to these methods, customer contribution margin accounting and the calculation of customer equity or of Customer Lifetime Value (CLV) are possible tools to measure customer performance and customer attractiveness. By responding to central questions of each tool (see Figure 88) and defining adequate Key Customer Performance Indicators (KCPI), companies can enhance their customer perform- ance measurement in order to improve the quality and profitability of customer relationships. In addition, customer performance measurement enables fuzzy customer segmentation, which is defined as the fuzzy classification of the company’s current customers into similar, fuzzy segments, using different customer performance indicators. - 112 - Chapter 7: Conclusion Customer Performance Measurement (CPM) and management C2) Fuzzy scoring or RFM method Customer contribution margin analysis (Section 3.4) Section 3.5) (Subsection 5.1.14) Cumulative turnover/profit C1) C6) C4) Indicator X C2) C3) Which performance indicators are considered in fuzzy portfolios? What are the membership degrees of one/all customers to each class? How can the portfolios be optimised? C4) C7) C3) Fre- Cum. share of customers Who are the customers with the highest/lowest turnover or profit? How many customers generate how much of the turnover or profit? How are A-, B- or Ccustomers managed? C1) quency Which indicators are considered in the scoring model & how weighted? Which customers purchase most recently, freqent and at a high value? Which incentives are offered to improve RFM? Calculation of customer equity and Customer Lifetime Value (CLV) (Subsection 5.1.16) (Rt − Et ) t t =0 (1 + i ) n CLV = ∑ How can customer contribution margins I-IV can be improved? Which (non-/)monetary indicators are taken into account to model and calculate CLV or customer equity? Measurement level Examples of indicators r Customer results Customer Investment Indicators (CII) Customer Relationship, Recommendation, Information, and Cooperation Indicators (CRI, CInfI, CReI, CCR) Category C8) B-customers A-customers C-customers C5) Monetary value (Section 3.2) Indicator Y Fuzzy customer ABC-analysis Recency Fuzzy customer portfolio analysis (Section 4.3) Customer Performance Indicator for Revenues and Profitability (CPIP) Customer Performance Indicators (CPIs) Central questions Fuzzy customer analysis (= analysis, planning, implementation and control) q Customer behaviour pBehavioural intentions o Customer attitude n Customer investments Turnover (I 31), cash flow (I 30), contribution margins I-IV (I 70 - I 73), customer gross or net profit (I 75,I 76), customer equity, CLV (I 79,I 80), # of new customers (I 4), # of customers (I 7), market share (I 43) Repurchases (recency, frequency, rhythm; I 20-I 28), cross-/up-selling (I 50-I 53), share of wallet, penetration (I 39,I 38), payment behaviour (I 66), recommendations (I 156), complaints (I 164), duration of CR (I 147) Repurchase intentions (I 55), cross-buying intentions (I 54), intention to recommend (I 151), intention to switch (I 141), customer loyalty (I 134), intention to dialog (I 157), intention to cooperate (I 171) Perceived product (I 118), service (I 120) and relationship quality (I 149), or price-performance ratio (I 122), image (I 115), customer value (I 123 I 125), customer satisfaction (I 126), commitment (I 131), trust (I 133) Marketing costs (I 101), total customer costs (I 102), acquisition, retention and recovery costs (I 87-I 92) administration (I 93), transaction (I 94), contacts (I 100), (after) sales (I 95), logistic (I 96), service (I 97) costs Figure 88: Tools and Indicators for Customer Performance Measurement Two different approaches can be used to define fuzzy segments. Any class of a one-, two- or multidimensional fuzzy classification can be defined as a fuzzy customer segment. Another way is to define fuzzy clusters according to the patterns of the data, using fuzzy algorithms. The definition of fuzzy segments has important outcomes. Firstly, customers can partly belong to different segments at the same time. If customer strategies are assigned to fuzzy segments, customers have to be managed according to several, may be contradictory strategies at same time. This forces customer managers to combine, align and personalise customer strategies. However, to avoid contradictions, basic requirements should be well defined. For instance, the company defines the basic requirement that a customer has to be profitable in the long term or that his creditworthiness has to exceed a certain level. - 113 - Chapter 7: Conclusion Further points about fuzzy customer segmentation are summarised in Table 23. Table 23: Results of Research Question 6 How can customers be segmented fuzzily? (¨Section 5.1) Fuzzy customer segmentation can be realised by one-, two- or multidimensional fuzzy classification using fuzzy classification management tools (¨RQ 2) and CPIs or KCPIs (¨RQ 5). Customer segmentation and the management and profitability of customer relationships can be improved using portfolio analysis with important indicators (¨Subsections 5.1.5 to 5.1.16): 6 - fuzzy classified customer orientation and customer value portfolios - fuzzy classified customer satisfaction portfolios - fuzzy classified customer loyalty and retention portfolios - fuzzy classified customer repurchases, add-on selling and share of wallet portfolios - fuzzy classified customer turnover, contribution margins and profit portfolios - fuzzy classified customer equity and Customer Lifetime Value (CLV) portfolios. This thesis suggests to classify and segment all customer performance indicators fuzzily in order to avoid misclassifications and to improve the quality of customer evaluations. Customer segmentation often is a strategic task in firms: banks and other financial institutions, for instance, have to segment ‘creditworthy’ loan applicants from ‘not creditworthy’ ones. By defining a four-level hierarchy of creditworthiness with different practice-relevant criteria in Section 6.2, a fuzzy credit scoring approach was applied to the rating of a loan applicant’s personal, material and overall creditworthiness. In addition, a multidimensional fuzzy credit rating approach allows to calculate individual interest rates (risk premiums) according to the customer’s values of the attributes ‘creditworthiness’, ‘amount of credit’ and ‘credit period’. Table 24 summarises further points. Table 24: Results of Research Question 7 What are the benefits of the fuzzy classification approach in credit rating? (¨Section 6.2) The decomposition principle applied to a fuzzy credit scoring model enables a fair and exact credit rating of loan applicants on different levels of a hierarchy of creditworthiness. A three-dimensional fuzzy classification model allows to calculate individual interest rate according to the values of the attributes ‘creditworthiness’, ‘amount of credit’ and ‘credit period’. The decision to allow a credit is sharp, but contractual terms/conditions can be adapted fuzzily. 7 Conclusion: fuzzy classification enables - a fair, exact, differentiated and sensitive rating of loan applicants according to the default risk - the reduction of misclassifications (that a loan applicant receives no credit although he is creditworthy, or that a loan applicant receives a credit, although he is not creditworthy) - an improvement of the risk structure of the whole credit portfolio and - the mass customisation of products and services in banking. - 114 - Chapter 7: Conclusion 7.2 Critical Remarks As summarised in this chapter, the application of fuzzy classification has many advantages. However, fuzzy classification is also confronted with certain problems: Sharp classification usually is clear, simple, straightforward and understandable for every- one. In contrast, fuzzy classification is more complicated and not as easy to understand, to communicate and to implement as sharp classification. If a classified customer belong simultaneously to different classes and strategies, this can be confusing, indeed. How can it be explained to customer Brown that he was fuzzy classified into different classes at same time and therefore receives a personal discount of 7.4% or has to pay an interest rate of 8.59%? Since many people do not like being classified or labelled as something and may not understand or accept this, one strategy could be not to communicate customer classifications. However, fuzzy classification may has to be communicated in a subtle, indirect way, writing, for example: “Dear Mr. Brown, our company thanks you for your trust and loyalty and offers you a personal discount of 7% for your next purchase.” The communication of the fuzzy classification concept to employees can be difficult as well. However, to successfully realise fuzzy customer segmentation, all relevant people have to understand and support the idea and the implementation of fuzzy classification. The benefit of a classification always depends on the context. It can be inefficient to clas- sify objects, if the monetary or non-monetary, direct or indirect costs of classification are too high in comparison to the benefit of the classification. Possible classification costs are: - time required to collect, gather, handle, store, administrate and classify (customer) data - staff (e.g. CIO, CCO, customer managers, data architect, employees of CRM or IT) - ICT, technical infrastructure; hardware, information systems, CRM software, etc. If an entrepreneur and the employees of a small enterprise personally know very well their customers and their different value for the company, (fuzzy) classification with a data mining tool is not necessary. However, with an increasing number of anonymous customers in medium or large enterprises, such implicit customer evaluation and segmentation is often not possible anymore. This means that the benefits of CRM and of fuzzy customer classification or segmentation for information management is higher with a large number of customers. It is theoretical and empirical difficult to weight attributes or criteria optimally, for instance to define the right degree of gamma or the number of points to each class of a scoring model. Many basic decisions in everyday and business life have to be made in a sharp manner. For example: a relationship is continued, or it is not. A contract is signed, or it is not; an order is accepted, or it is not. However, such sharp decisions do not exclude that for instance the terms or the conditions of a contract or of an order still can be adapted in a fuzzy way. - 115 - Chapter 7: Conclusion Considering customer performance measurement, the following points have to be commented: Much intangible, but important customer information cannot be handled by Customer Per- formance Measurement (CPM) or by a system (CPMS). In the words of Albert Einstein: “Sometimes what counts can’t be counted, and what can be counted doesn’t count.” Consequently, the measurability of customers, or of marketing in general, is a problem and challenge of marketing controlling. An empirical study of the market research organisation IHA-GfK and the Swiss Marketing Association (GfM) confirms this problem (see Figure 89). 56 Measurability of marketing Basis of information and data on marketing 37 Know-how in the range of marketing 19 Lack of ressources for marketing controlling 18 Indifferent No challenge 19 26 46 23 Cross-functional support of marketing controlling Big challenge 44 28 Engagement of marketing and sales management for marketing controlling 12 32 33 44 36 45 37 45 0% 100% Source: [Reinecke and Herzog 2006, p. 87] Figure 89: The Main Challenges of Marketing Controlling in Practice In addition, the basis of information and data on marketing and customers is challenge as well, as shown in Figure 89. However, both the measurability of marketing or CRM and the basis of information can be improved by clearly defining and operationalising (customer) performance indicators, as proposed in this thesis. It is methodically difficult to determine cause-and-effect relations between the indicators in models of performance measurement (see e.g. [Malina and Selto 2004]). Consequently, causalities as proposed in the "big CRM success chain" have to be analysed critically. The exact profit or equity of a customer cannot be determined, because not all customer costs, revenues or benefits can be assigned clearly to a single customer or to a marketing decision, process or action. CPM(S) is only one instrument of CRM, customer and marketing controlling and should not be considered or implemented in an isolated manner. CPM and customer performance indicators are not an end in itself: they have to support profitably marketing and business or corporate strategies. - 116 - Chapter 7: Conclusion 7.3 Outlook Many questions about fuzzy classification still are to be answered. Following open-ended questions are only few ideas for further research on fuzzy classification in the field of CRM. How could a customer Data Warehouse (DWH) with fuzzy classes be used for Customer Performance Measurement (CPM)? How has the architecture of a DWH to be designed? How can an open source DWH be adapted and implemented in an analytical CRM system? What has to be considered from the information technology, and what from the business management point of view? What are the advantages and problems of such a Customer Performance Measurement System (CPMS) or of a DWH for information management? How do CPMS or DWH architectures in business practice look like? How could a hierarchical multidimensional fuzzy classification be combined with a scor- ing model to evaluate customers in business practice? How do performance indicators have to be aggregated and weighted (with points or the y-operator), to receive a valid valuation method to classify fuzzily, for instance, customer attractiveness or customer equity? How could sharp and fuzzy classification be combined in order to improve managerial de- cisions? How can basic requirements, which have to be fulfilled sharply (e.g. a customer has to be profitable in the long-term), be optimally defined within a fuzzy classification? How does a fuzzy credit rating model for business customers or enterprises could look like? Which rating criteria, figures, ratios and measures of companies have to be considered in a hierarchical fuzzy classification of credit rating? What is the benefit of a fuzzy rating of securities, stocks and bonds in the fields of finance and investment? Unfortunately, this master thesis could not realise empirical studies about the business ap- plications for fuzzy classification. Future empirical research and case studies may focus on the implementations of the fCQL toolkit in firms to demonstrate the discussed advantages of fuzzy portfolio analysis, fuzzy ABC analysis and fuzzy customer segmentation or evaluation. Since little theoretical and empirical research has been done on market- or customer-oriented performance measurement, the following questions raised: How many and which indicators are used for CPM in business practice? Which indicators are important in companies of different sizes and in different industries? How and why can customer performance indicators support CRM or marketing controlling in daily business? What are Key Customer Performance Indicators (KCPIs; "indicators that matter") of suc- cessful companies in general or in different industries, and why do they matter? How have customer performance indicators to be defined, operationalised, implemented, analysed and controlled specifically? Empirical research and case studies of companies may answer these questions and provide valuable information in oder to improve CRM. - 117 - References and Further Reading A [Aksoy et al. 2007] Aksoy, L., Bejou, D., Keiningham, T. 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The file is available under: www.dzumstein.ch/pdf/GammaOperator.xls (or on the CD-ROM enclosed on the back) Screenshot 1 of GammaOperator for the Calculation of Smith’s Membership Degrees in Table 3 Enter Grade: investment (in Section 3.2), personalised account, interest rate, … Enter value of the classified element to attribute 1 Enter value of the (vertical y-axis) classified element to attribute 2 (horizontal x-axis) Enter the value of gamma (γ) of the γ-operator (see page 12) Result: absolute Membership Degrees (MD) M(Oi│Ck) Result: normalised Membership Degrees (MD) Mnorm(Oi│Ck) Result: investment, personalised account or interest rate, … Screenshot 2 of GammaOperator for the Calculation of Smith’s Membership Degrees in Table 4 Enter value of the classified element to attribute 1 (vertical y-axis) Enter value of the classified element to attribute 2 (horizontal x-axis) Enter value of the classified element to attribute 3 (z-axis) - 133 - Results: e.g. calculation of RFM points (in Section 3.5) Appendix Appendix 2: Checklist for Performing – Fuzzy Strengths/Weaknesses Analysis 1 μ high performance μ low performance 0 Minor Major Major Minor weakness weakness Neutral strengths strengths Marketing 1) Company reputation 2) Market share 3) Customer satisfaction 4) Customer retention 5) Product quality 6) Service quality 7) Pricing effectiveness 8) Distribution effectiveness 9) Promotion effectiveness 10) Sales force effectiveness 11) Innovation effectiveness 12) Geographical covarage 1 0 μ high importance μ low importance Very low Low Performance Medium High Very High Importance Finance 13) Cost or availability of capital 14) Cash flow 15) Financial stability Manufacturing 16) 17) 18) 19) 20) 21) Facilities Economics of scale Capacity Able, dedicated workforce Ability to produce on time Technical manufactering skill Organisation 22) 23) 24) 25) Visionary, capable leadership Dedicated employees Entrepreneurial orientation Flexible or responsive Source: adapted from [Kotler and Keller 2005, p. 55] 134 Appendix Appendix 3: Value Factors from the Customer Perspective Value Factor Literature Reference Price, monetary sacrifices [Zeithaml 1988], [Parasuraman et al. 1988, 1994], [Monroe 1990], ; [Claycomb and Franckwick 1997], [Rust et al. 2000] Cost reduction, decreased relationship costs References, image, status, prestige Relationship investments (time, ressources) Time Effort, search effort Energy Psychological costs, physic costs Indirect costs Service provider’s reliability Service provider’s responsiveness, quick response time Accuracy Flexibility Efficency Service delivery Methodology used Problem identification Assurance Empathy Seller’s / Service provider’s competence, core competencies Service provider’s network (firm/personal) Service provider’s innovation, creativity Service provider’s knowledge strategy Service provider’s expertise, knowledge Service provider’s experience Safety Credibility Security Trust Stability Continuity Goals, goal compatibility Bonds (structural, social, economic) Brand fC [Wilson and Jantrania 1996] ; [Claycomb and Franckwick 1997] ; [Wilson and Jantrania 1996], [Claycomb and Franckwick 1997] ; [Parasuraman et al. 1988, 1994], [Rust et al. 2000] [Parasuraman et al. 1994], [Claycomb and Franckwick 1997] [Parasuraman et al. 1988, 1994] [Grönroos 1998], [Claycomb and Franckwick 1997] [Grönroos 1992] [Parasuraman et al. 1988, 1994] ; ; ; ; ; ; [Parasuraman et al. 1988, 1994], [Maister 1993] ; [Grönroos 1992] [Grönroos 1992] [Grönroos 1992] [Zeithaml et al. 1990], [Rust et al. 2000] [Patterson and Spreng 1997] [Patterson and Spreng 1997] [Parasuraman et al. 1988, 1994] [Parasuraman et al. 1988, 1994] ; ; ; ; ; ; ; ; [Patterson and Spreng 1997], [Wilson and Jantrania 1996] ; [Patterson and Spreng 1997], [Hansen et al. 1999] [Maister 1993] [Hansen et al. 1999] [Maister 1993] [Maister 1993] [Ravald and Grönroos 1996] [Ravald and Grönroos 1996] [Ravald and Grönroos 1996] [Ravald and Grönroos 1996], [Wilson and Jantrania 1996] [Grönroos 1992] [Grönroos 1992] [Wilson and Jantrania 1996] [Wilson and Jantrania 1996] [Rust et al. 2000] ; ; ; ; ; ; ; ; ; ; ; ; ; ; Source: adapted from [Leino 2004, pp. 45f] :: Fuzzy classification not adequate ;: Fuzzy classification with discrete or ;: continuous membership functions possible 135 Appendix Appendix 4: 170+ Customer Performance Indicators Legend measuring unit: # = Number/count, € = in euro, % = Percentage/share, Ø = Average (per customer), I = Index, ∑ R = Rating, t = time/period, * = Aggregate value (at enterprise level), * = Indicator at a customer level and at enterprise level Indicators for: customer investment; customer attitude; customer behavioural intentions; customer behaviour; customer results Indicators in bold: important indicators often discussed in literature on marketing or accounting :: Fuzzy classification not adequate ;: Fuzzy classification with discrete or ;: continuous membership functions possible I# Indicator Definition or operationalisation Unit Purpose fc 1) Customer Performance Indicators for Revenue and Profitability (CPIP) I1 I2 I3 I4 I5 I6 I7 I8 I9 I 10 I 11 I 12 I 13 I 14 I 15 I 16 I 17 I 18 I 19 I 20 I 21 I 22 I 23 I 24 I 25 I 26 I 27 I 28 I 29 I 30 I 31 Number of interested non-buyers, pro- #,%, Indicator for market potential and ∑ ; spective customers for the company * the company’s potential growth Number of new customers relative to Indicator for customer acquisition & %,* Conversion rate ; prospective customers marketing/communication success Number of customers, who are gained #,%, Indicator competitive position and Poached customers from competitors of from the competitors in a period ∑ ; t, * for relative market share (growth) Number of new customers in a period, #,%, Indicator for customer acquisition & Number of new customers ∑ ; nominal or relative to custom. portfolio t, * marketing success; future revenue Number of new customer in a period #,%, Benchmark for competitive position Relative number of new customers ∑ in comparison with main competitors t, * & for customer acquisition success ; Number of first-time customers of a #,%, Over time sales should rely not on Number of first-time buyers ∑ ; product (nominal/relative to cu. base) t, * trial but on repeat buyers Number of customers who bought #,%, Indicator for loyalty and retention, Number of customers ∑ from the company in a defined period t, * market share, competitive position ; Number of repeat buyers of a product #,%, Indicator for customer satisfaction, Number of repeat buyers ∑ (nominal/relative to customer base) t, * loyalty/retention, stability of a sales ; Number of regual buyers (patrons) of #,%, Indicator for loyalty/retention & for Number of regular buyers ∑ a product (nominal/relative to base) t, * the stability of sales and revenues ; Number of migrated or lost customers #,%, Indicator for customer dissatisfacNumber of migrated customers ∑ (nominal or relative to customer base) t, * tion, disloyalty or switching barriers ; Number or rate of recovered custo#,%, Indicator for customer recovery or Number of recovered customers ∑ ; mers (nominal or relative to cu. base) * churn management success Number of very profitable recovered #,%, Indicator for customer recovery Number of profitable recovered cu. ∑ ; customers (nominal or relative) €,t, * success and efficiency Number of customer’s bookings or re- #,%, Leading-indicator for customer Number of bookings or reservations servation by the company in a period €,t,* turnover, contr. margins and profits ; Number of customer’s requests, #,%, Indicator for customer’s interest for Number of requests tenders or inquiries in a period €,t,* a product and purchase intention ; Share or number of responses to #,%, Indicator for customer orientation Perfect response customer requests in a defined period €,t,* and the capacity to serve customer ; Number of company’s offers, bids or #,%, Indicator for company’s marketing Number of offers ; quotations to a customer in a period €,t,* and sales effort Number of customer’s orders or ap#,%, Leading-indicator for customer Number of orders pointments by the company in a period €,t,* turnover, contr. margins and profits ; Number of correct, complete and #,%, Indicator for the company’s capacPerfect orders ; punctual deliveries to a customers €,t,* ity to serve customers Number of customer’s orders (I 17) Indicator for customers satisfaction %,* Order quote (hit rate) relative to number of requests (I 14) with the offer & offering efficiency ; Purchased products/services (nom#,€,Ø, Indicator for marketing and sales Purchased products or services ; nal/relative) of a customer in a period %,t,* success and actual revenues Customer’s purchased volume of a #,€, Indicator for purchase behaviour, Purchased volume product or service per purchase/total Ø,%,t marketing success, actual revenue ; Customer purchases of a product com- #,€, Indicator for relative intensity of Heavy usage index pared a Ø customer in the category Ø,I,* consumption (purchase behaviour) ; Average order value of a customer €,Ø, Indicator for customer purchase Average order value per purchase in a defined period t,* behaviour; turnover, potential, CLV ; Dates (dd.mm.yyyy) of a customer’s Indicator for customer purchase Ø,t,* Purchase dates : purchases of company’s products behaviour Rhythm or regularities of customers Indicator of customer usage and Ø,t,* Purchase rhythm ; purchases in a defined period purchase behaviour Customer’s intensity, e.g. number, vol- I,R, Indicator for customer usage and Purchase intensity ; ume or value of purchases in a period t,* purchase behaviour The length of time since a customer’s Indicator for purchase behaviour & t,Ø,* Recency ; last purchase (RFM method) for number of active customers Frequency of a customers purchases Indicator for customer behaviour t,Ø,* Frequency ; in defined period (RFM method) for customer loyalty or retention Monetary value of a customer’s total €,Ø, Indicator for customer turnover, Monetary value ; purchases in a period (RFM method) R,* profitability and CLV Operiational (free) cash flow received Indicator for customer payment €,t,* Cash flow ; from a customer in a defined period behaviour Customer’s total turnover (here synon- €,%, Indicator for company’s ability to Customer turnover (or sales) ; ymously: sales/revenues) in a period Ø,t,* fulfil customer needs, create value Number of prospective customers 136 Appendix I 33 I 34 I 35 I 36 I 37 I 38 I 39 I 40 I 41 I 42 I 43 I 44 I 45 I 46 I 47 I 48 I 49 I 50 I 51 I 52 I 53 I 54 I 55 I 56 I 57 I 58 I 59 I 60 I 61 I 62 I 63 I 64 I 65 I 66 I 67 I 68 Amount of turnover of a first-time €,Ø, Indicator for customer potential ; buyer (of a new customer) in a period %,t,* and attractiveness Amount of turnover of a regular €,Ø, Indicator for customer potential, Turnover of repeat/regular buyers ; customers in a defined period %,t,* attractiveness and profitability Total, cumulative turnover (or sales) €,Ø, Indicator for loyalty and customer Cumulative turnover (or sales) of a customer since his first purchase %,t,* lifetime value or customer equity ; Customers sales growth (nominal or %, Indicator for customer potential Growth of turnover (or sales) ; relative to total sales growth) Ø,* and attractiveness Sales premiums or promotional ince- #,€,Ø, Customer investment indicator to Sales premiums ; tives given to cu. for buying a product %,t,* influence purchase behaviour Discounts, reductions or gifts given to #,€,Ø, Customer investment indicator to Customer or new customer discounts (new) customers dependent on sales %,t,* acquire new customers ; Share of demand of all products a Indicator for commitment (I 131) & %,* Customer penetration customer buys from the company customer (add-on selling) potential ; Share of customer’s fulfilment by the #,€,Ø, Indicator for commitment (I 131) Share of wallet ; company rel. to demand of a product %,* and (repurchase) potential Share of a new customer’s fulfilment #,€,Ø Indicator for usage behaviour, Share of wallet of new customers ; of demand relative to his total demand ,%,* customer turnover and potential Customer’s share of wallet relative to %, Benchmark for the company’s Relative share of wallet ; company’s main competitor(s) €,* competitive position Share of customer’s volume at the #,€, Indicator for the dependency of the Market share of customer ; total (revenue/unit) market share %,* company on a customer Sales revenue or unit sales as a #,€, Indicator for market strength and Revenue/unit market share ∑ ; percentage of market sales revenue %, * competitive position Company’s market share divided by #,€, Indicator for market strength and Relative market share ∑ ; largest competitor’s market share %, * competitive position Growth of revenue/unit (I 43) or re#,€,Ø, Indicator for marketing success Growth of market share ∑ ; lative market share (I 44) in a period %,t, * and industry attractiveness Nominal or relative growth of the total #,€,Ø, Indicator for industry attractiveness Market growth ∑ ; market demand of a product/category %,t, * and market potential Describes the total demand of all #,€,Ø, Indicator for customer need and Market demand ∑ ; consumers for a product in a period %,t, * wishes (industry attractiveness) Purchasers of a product category as Indicator for (product/service) ca∑ %, * Market penetration ; a percentage of total population tegory acceptance by consumers Market share of a product in comparIndicator for the brand/product ∑ %, * Brand/product penetration ; son to total market share of a product acceptance by consumers Number of additional but less ex#,€,Ø, Indicator for customer satisfaction, Down-selling (rate) ; pensive products sold to a customer %,t,* loyalty or retention, and turnover Number of customer’s purchases of #,€,Ø, Indicator for customer satisfaction, Cross-selling (rate) ; different products from the company %,t,* loyalty or retention, and turnover Probability of selling additional, other %,€, Indicator for customer’s potential, Cross-selling potential ; products to an existing customer R,t,* future turnover and profits Number of additional, upgrade, more #,€,Ø, Indicator for customer satisfaction, Up-selling (rate) ; expensive products sold to a customer %,t,* loyalty or retention, and turnover Expressed intention of customer to #,€,Ø Leading-indicator for customer’s Cross-buying intention ; purchase different products ,%,t,* future turnover and profits Expressed intention of a prospect or Leading-indicator for customer %,* Repurchase intentions ; customer to (re)purchase a product satisfaction, loyalty and retention Number of customer’s repurchases €,%, Indicator for customer value, satisRepurchases (or repurchase rate) ; (or repurchase rate) of a product Ø,t,* faction, loyalty and/or retention Probability of intention of existing Indicator for customer repurchases %,* Probability of repurchases customers to repurchase a product (satisfaction, loyalty or retention) ; Customer purchased product mix Indicator for customer needs, Customers product mix at company by the company or at the competitor #,€,* wishes and purchase behaviour : Customer’s average number/volume #,€, Indicator for customer needs, Average product portfolio of customer of purchases of products in a period ; Ø,t,* wishes and purchase behaviour Customers sensitivity to notice and Ø,I, Indicator for probability to switch or Price sensitivity ; react to changes in prices €,R,* repurchase and for loyalty The additional charge a satisfied cust- €, Indicator for product quality, cusPrice premium omer pays for a product or service %,* tomer value, satisfaction & loyalty ; Method or medium, how a customer Indicator for purchase or payment -,* Method of payment pays, e.g. cash, credit card, cash card behaviour and for creditworthiness : Number of days, weeks or months of #,Ø, Indicator for customer creditworPunctuality of payment ; a customer’s delay in payment t,* thiness and solvency A customer’s total number and sum #,€, Indicator for customer creditworNumber or sum of outstanding bills ; of outstanding bills or accounts Ø,t,* thiness and solvency Amount or share of customer’s or #,€,% Indicator for customer creditworAmount or share of bad debt losses new customer's with bad dept losses Ø,t,* thiness and solvency ; Customer’s payment history or Ø,t, Indicator for customer creditworPayment history ; punctuality of payment in a period I,R,* thiness and solvency A new customer’s payment history Ø,R, Indicator for customer creditworPayment history of new customers ; or punctuality of payment in a period t,* thiness, solvency Customer’s creditworthiness or Ø,I, Indicator for the ability, intention Creditworthiness credit rating; customer solvency R,* and financial capability to pay bills ; Turnover of first-time buyers Add-on-selling I 32 137 Appendix I 69 I 70 I 71 I 72 I 73 I 74 I 75 I 76 I 77 I 78 I 79 I 80 I 81 I 82 I 83 I 84 I 85 I 86 Customer’s total turnover (or sales) €,% Indicator for customer turnover, fix minus total variable costs in period Ø,t,* costs and profit Customer’s turnover (net sales) minus €,% Indicator for customer turnover Customer contribution margin I costs of goods/services sold in period Ø,t,* and profit Contribution margin I (I 70) minus €,% Indicator for customer turnover, Customer contribution margin II marketing costs (I 101) Ø,t,* marketing costs and profit Contribution margin II (I 71) minus €,% Indicator for customer turnover, Customer contribution margin III customer-driven sales costs (I 95) Ø,t,* marketing costs and profit Margin III (I 72) minus customer driven €,% Indicator for customer turnover, Customer contribution margin IV transport & service costs (I 96, I 97) Ø,t,* transport/sales costs and profit Contribution margin (I-IV) of a new €,% Indicator for customer turnover, Contribution margin of new customer customer in a defined period Ø,t,* customer lifetime value, potential Customer’s total turnover (I 31) minus €,Ø, Indicator for customer and comCustomer gross profit total costs (I 102) in a period t,* pany performance and success Gross profit (I 75) minus taxes, int€,Ø, Indicator for customer and comCustomer net profit erests, depreciation & other expenses t,* pany performance and success Realised (or expected) positive or €,Ø, Leading indicator for potential and Growth of customer profit negative growth of gross or net profit t,* company performance or success Difference between total turnover and €,%,Ø Indicator for customer and comCustomer profitability costs associates with a CR in a period t,R,* pany performance and success The total of the discounted lifetime €,%,Ø Indicator for customer and comCustomer equity values of all customers of a company t,R,* pany performance and success The present, discounted value of all €,%,Ø Indicator for customer and comCustomer Lifetime Value (CLV) cash flows over the length of the CR t,R,* pany performance and success The present value of all cash flows €,%,Ø Indicator for prospect potential and Prospect Lifetime Value (PLV) over the length of the prospect’s CR t,R,* future customer lifetime value The degree of overall attractiveness Indicator for customer & company I,R,* Customer attractiveness of a customer for a company performance (for segmentation) The customer’s future potential, e.g. €,I, Indicator for future customer and Customer potential for sales, contribution or profit R,t,* company performance or success A new customer’s future potential, e.g. €,I,Ø, Indicator for future customer and Potential of new customers volume, sales, contribution or profit R,t,* company performance or success The change of customer’s potential €,I, Indicator for future customer and Development of customer’s potential in a defined past or future period R,t,* company performance or success The change of customer’s potential €,I, Indicator for future customer and Development of customer’s industry in a defined past or future period R,t,* company performance or success Gross margin (contribution margin) ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; 2) Customer Investment Indicators (CII) I 87 Acquisition costs I 88 Acquisition efficiency I 89 Retention costs I 90 Retention efficiency I 91 Recovery costs I 92 Recovery efficiency I 93 Administration costs I 94 Transaction costs I 95 Sales costs I 96 Logistic costs I 97 Service costs I 98 After sales costs I 99 Communication costs I 100 Contact costs I 101 Marketing costs I 102 Total customer’s costs I 103 Return on Sales (ROS) I 104 Return on Customer (ROC; ROCI) All costs incurred to acquire a new customer (e.g. advertising, marketing) Ratio of customer acquisition costs (I 87) to turnover of first buyer (I 32) All costs incurred to bind a customer (e.g. retention programs, offers) Ratio of customer acquisition costs (I 89) to sales of customers (I 34) All costs incurred to recover a customer (e.g. recovery actions, offers) Ratio of customer recovery costs (I 91) to sales of recovered customers Net costs of administration (wages of administrative staff, materials, etc.) All costs incurred in making an exchange of products or services All costs incurred to sale a product or service to a customer All costs associated with logistics (e.g. order, inventory, handling & delivery) All costs associated with customer service (e.g. call center, consulting) All costs incurred after the sale (e.g. warranty, helpdesk, complaints, etc.) All costs associated with customer communication (e.g. ad, mail, phone) All costs incurred to contact a customer (e.g. phone calls, travel expenses) Total expenditures on marketing activities in a defined period All customer-related costs in a defined period ROS is calculated by dividing net profits by sales (I 31: I 76) ROC is calculated by dividing cu. net profits by total costs (I 76: I 102) 138 €,%, Ø,t,* I,R, ∑ * €,%, Ø,t,* I,R,* €,%, Ø,* I,R,* €,%, Ø,t,* €,%, Ø,* €,%, t,* €,%, Ø,t,* €,%, Ø,t,* €,%, Ø,t,* €,%, Ø,t,* €,%, Ø,t,* €,%, Ø,t €,%, Ø,t,* %, ∑ R, * %, R,* Indicator for the company’s effort ; to acquire or gain new customers Indicator for the ability to acquire ; efficiently new customers. Indicator for the company’s effort ; to bind and obtain customers Indicator for the ability to bind ; efficiently current customers. Indicator for the company’s effort to recover or reactivate old customers ; Indicator for the ability to recover ; efficiently migrated customers. Indicator for customer orientation and for customer efficiency (I 108) ; Indicator for selling effort/efficiency & customer contribution margin III ; Indicator for selling effort/efficiency & customer contribution margin III ; Indicator of supply chain mmgt., & for customer contribution margin IV ; Indicator for customer orientation & customer contribution margin IV ; Indicator for customer orientation & customer contribution margin IV ; Indicator for the company’s market; ing effort and efficiency Indicator for customer orientation and for customer efficiency (I 108) ; Indicator for the marketing effort & ; customer contribution margin II Indicator for customer profitability ; and customer efficiency Indicator for the company’s ability ; to generate profits from sales Indicator for the company’s ability ; to generate profits from customers Appendix I 105 Return on Relationship (ROR) I 106 Return on Customer Satisfaction I 107 Return on Customer Retention I 108 Customer efficiency I 109 Return on Marketing (ROM; ROMI) I 110 Return on Investment (ROI) ROR is calculated by dividing cu. net profits by total costs (I 76: I 102) Net profits of customer satisfaction divided by cu. satisfaction mmgt costs Net profits of customer retention divided by cu. retention costs () Customer contribution margin relative to capacity shortage/costs Total revenues of marketing divided by total marketing costs Total revenues divided by total costs or investment %, R,* %, R,* %, R,* %, R,* %, R,* %, ∑ R, * Indicator for company’s ability to generate profits from relationships Indicator for the company’s ability/ effectiveness to satisfy customers Indicator for the company’s ability & effectiveness to bind customers The company’s ability to optimally serve customers at low costs Indicator for marketing efficiency and marketing success Indicator for efficiency and success of investments ; ; ; ; ; ; 3) Customer Relationship Indicators (CRI) Share of target customers which is %,€,Ø Indicator for advertising effects ; aware of a brand (recall/recognition) I,R,* and communication success Percentage of population/prospectives %,Ø, Indicator for advertising effects Ad awareness ; that is aware of a brand’s advertising I,R,* and communication success Percentage of customers who demoIndicator of the familiarity with a R,* Brand/product knowledge strate product knowledge or beliefs product beyond name recognition ; First brand comes to customers mind Indicator for the salience of a R,* Top of mind ; asking about a product of a category product or service Indicates, how a company is Indicator for customer satisfaction, R,* Corporate image perceived by a (prospective) customer repurchases and recommendation ; Indicates, how a company’s product is Indicator for customer satisfaction, R,* Product or service image perceived by a (prospective) customer repurchases and recommendation ; The a company’s focus on meeting Indicator for a company’s ability to R,* Customer orientation ; the needs and wants of it customers identify market opportunities A customer’s rating of the perceived Indicator for customer expectations R,* Perceived product quality quality of a given product. or satisfaction and product quality ; A customer’s rating of a product comBenchmark for customer expectaR,* Relative perceived product quality pared to other products in the market tions or satisfaction, product quality ; Customers perceived quality of a Indicator for customer expectations R,* Perceived service quality provided service or satisfaction and service quality ; Customers perceived cheapness or Indicator for the company’s price R,* Perceived cheapness/expensiveness expensiveness of a offer competitiveness (and satisfaction) ; Customer perceived price-perform%,I, Indicator for the company’s price Perceived price-performance ratio ance ratio or value for money. R,* competitiveness (and satisfaction) ; The (subjective) customer rating Indicator for created utility & (basic R,* Perceived value or utility about the perceived value of product /added) value of a marketing offer ; The total value that a customer Indicator for the created utility and R,* Customer value ; receives from a offer value of a marketing offer Degree of fulfilment of customers’ ex- Ø,I, Indicator for customer needs and Fulfilment of customers’ expectations pectations/requirements to a product R,* expectations, satisfaction & loyalty ; The overall customer satisfaction with Ø,I, Indicator for customer value and Customer satisfaction the offer of a company R,* likelihood of repurchases (loyalty) ; Customer satisfaction compared with Ø,I, Benchmark of the company’s Relative customer satisfaction ; competitors/national satisfaction index R,* ability to satisfy customers The degree of customer satisfaction Ø,I, Indicator for product quality and Customer satisfaction with product with a certain product or product R,* likelihood of repurchases (loyalty) ; The degree of customer satisfaction Ø,I, Indicator for service quality and Customer satisfaction with service ; with a service R,* likelihood of repurchases (loyalty) Activation level in purchase situations Indicator for relationship quality & R,* Customer involvement ; or emotional proximity to a product likelihood of repurchases (loyalty) A customer’s internal intention to Indicator for likelihood of repurchR,* Customer commitment ; continue a valuable relationship ases (loyalty) & recommendations Feelings of affection of a customer for Indicator for likelihood of repurchR,* Customer attachment ; the company and its products/services ases (loyalty) & recommendations Degree of customers trust or confiIndicator for relationship quality & R,* Customer trust ; dence in the company and products likelihood of repurchases (loyalty) Committed customer who repurchase Ø,I, Indicator for satisfaction, attachCustomer loyalty ; by the company and recommend it R,* ment , retention & future revenues Customer’s perceived dependency Indicator for the company’s switchI,R,* Customer perceived dependence ; on the company or on its products ing barriers and customer retention Company’s financial, informational or Indicator for number of customers I,R Dependency on a customer ; cooperative dependency on customer and market share of customer The number of customers retained %,Ø, Indicator for satisfaction, loyalty or Customer retention (retention rate) (relative to the customer base) ; I,R,* ability of the firm to bind customers Retention rate in consideration of nonIndicator for satisfaction, loyalty or I,R,* Adjusted customer retention rate influence able migration (e.g. deaths) ability of the firm to bind customers ; Retention rate (I 137) weighted e.g. Indicator for the ability of the firm I,R,* Weighted customer retention rate ; by customers turnover or profit to bind profitable customers Customers basic willingness to switch Leading-indicator for customer I,R,* Willingness to switch from the company to a competitor loyalty, retention and lifetime value ; I 111 Awareness (brand awareness) I 112 I 113 I 114 I 115 I 116 I 117 I 118 I 119 I 120 I 121 I 122 I 123 I 124 I 125 I 126 I 127 I 128 I 129 I 130 I 131 I 132 I 133 I 134 I 135 I 136 I 137 I 138 I 139 I 140 139 Appendix Customers intention to switch over from the company to a competitor Customer’s future probability of Switching probability switching to a competitor Period, after which the half of all Customer half-life acquired customers have left again Number of migrated customers Churn rate (migration rate) relative to customer base Height of the company’s different Switching costs (switching barriers) switching barriers (or switching costs) Height of technical/contractual switchTechnical/contractual switching costs ing barriers (others barriers see p. 74) Length of time (weeks, months) of a Duration of customer relationship company’s relationship with customer Intensity or strength of the company’s Intensity of customer relationship relationship with a customer Customer’s perceived (subjective) Perceived relationship quality relationship quality with the company Cust. lifetime cycle: entrance, growth, Position in customer lifetime cycle maturation, saturation and dissolution I 141 Intention to switch I,R,* I 142 %,* I 143 I 144 I 145 I 146 I 147 I 148 I 149 I 150 I,R, ∑ * %,I, ∑ R, * I,R,* I,R,* Ø,t, R,* R,* I,R,* R,* Leading-indicator for customer loyalty, retention and lifetime value ; Leading-indicator for customer loyalty, retention and lifetime value ; Indicator for number of migrated customer and loyalty or retention ; Indicator for customer loyalty and retention (ability to bind customers) ; Indicator for customer retention & ; customer lifetime value or equity Indicator for customer retention & ; customer lifetime value or equity Indicator for customer satisfaction, loyalty, retention and lifetime value ; Indicator for relationship quality, and customer attachment & loyalty ; Indicator for service/product quality, satisfaction, loyalty and retention ; Indicator for cross-/up-selling potential & customer lifetime value ; 4) Customer Recommendation Indicators (CReI) I 151 Intention to recommend I 152 Number of recommendations I 153 Recommendation intensity I 154 Recommendation frequency I 155 Potential reference recipients I 156 Role as opinion leader Customers’ intention or plan to recommend products to friends, relatives,... Number of successful recommendtions of a customer in a given period Intensity of customer’s recommendation to friends, relatives,… Frequency and rhythm of a customer recommendation to friends, relatives… Number and importance of potential of a customer Customer’s social, medial or public position; influence to other consumers R,* #, R,* R,* #, R,* #, R,* R,* Indicator for customer satisfaction, commitment and loyalty Indicator for customer satisfaction, loyalty and acquisition efficiency Indicator for customer satisfaction, commitment and loyalty Indicator for customer satisfaction, commitment and loyalty Indicator for customers social position and role as opinion leader Indicator for product or corporate image, brand/company awareness ; ; ; ; ; ; 5) Customer Information Indicators (CInfI) Customers general intention/ willingIndicator for involvement, relationR,* ; ness to have a dialog or conversation. ship quality & response behaviour Consulting intensity (in hours or €) of #,€, Indicator for customer orientation, Consulting or helpdesk intensity ; a consultant or employee in a period R,t,* relationship intensity and quality Number of customer initiated contacts #,€, Indicator for different customer Customer initiated contacts to the company in a defined period R,t,* behaviour (sales, satisfaction, etc.) ; Number of customer initiated contacts #,€, Indicator for customer orientation Company initiated customer contacts to the company in a defined period ; R,t,* and intensity of relationship Number of companies contacts with #,€, Indicator for customer orientation Contact intensity with new customers a new customers in a defined period R,t,* and intensity of relationship ; Number of contacts with a customers #,€, Indicator for customer orientation Contact intensity with customers ; (regular buyer) in a defined period R,t,* and intensity of relationship Number, quality and importance of a #,R, Indicator for customer satisfaction Number/quality of suggestions ; customer’s suggestions in a period t,* and product expertise Number and quality of customer’s #,Ø, Indicator for product/service quality Number/quality of complaints complaints in a defined period R,t,* and customer satisfaction/loyalty ; Degree of customer’s satisfaction with R, Indicator for service quality and Complaint satisfaction company’s reaction to the complaint Ø,* customer satisfaction and loyalty ; Customer’s demands (e.g. numbers, #,€,Ø, Indicator for usage behaviour, Demands of technical services duration, costs) of technical services R,t,* satisfaction and product expertise ; Customer’s number/value of returned #,€,R, Indicator for product/service quality Number of returns (return rate) ∑ or rejected products or services t,* * and cust. expectations/satisfaction ; Customers know-how or expertise Indicator for usage behaviour, R,* Product expertise ; concerning the company or products experience and involvement Percentage of customers respond to %,I, Indicator for customer purchase beResponse rate or behaviour a communication or marketing action R,* haviour, value, purchase intention ; Customer’s response probability to a %, Indicator for response rate and Response probability ; future communication/marketing action R,* communication success I 157 General intention to dialog I 158 I 159 I 160 I 161 I 162 I 163 I 164 I 165 I 166 I 167 I 168 I 169 I 170 6) Customer Cooperation Indicators (CCI) I 171 Intention to cooperate I 172 Expertise for cooperation I 173 Potential cooperation topics Customer’s intention for a cooperLeading-indicator for attachment, R,t,* tion with the company (e.g. for R&D) relationship quality and intensity Customer’s know-how, knowledge, exIndicator for purchase behaviour, R,* pertise or information for cooperation relationship quality and intensity Possible cooperation topics, fields, Indicator for purchase behaviour, R,* technologies, products/services, etc. relationship quality and intensity ; ; ; Source: partly adapted from [Reinecke 2004, pp.267ff], [Neckel and Knobloch 2005, pp.199], [Bauer et al. 2006, pp.106ff], [Farris et al. 2006, pp.12ff, 129f], [Davis 2006, pp.4ff] 140 Appendix Appendix 5: Criteria for Fuzzy Market Segmentation Demographic Geographic Variables Geographic units Climate Regions City or metro size Population density Employment Age Gender Race Nationality Religion Generation Occupational group Occupation Family life cycle Family size Education Social class Psychographic Income Psychographic lifestyle Personality Sinus-Milieus® Social status Basic values 10 Milieus Euro-Socio-Styles ® Reality vs. mirage Permanence/change 8 Styles Behavioural Behavioural occasions Benefit Buying behaviour, Price sensibility Service sensibility Brand awareness Demand for quality Involvement Typical breakdowns fC Nations, states, cantons, regions, cities, communes, neighbourhoods, streets Northern, southern South-north, west-east (e.g. German speaking part of Switzerland, Romandy, Ticino, Grisons); mountains, midland <5000, 15’000-20’000, 20’001-50’000, 50’000-100’000, 100’001-200’000, 200’001500’000, 500’000-1Mio., >1Mio, ... Rural, suburban, urban; Resident persons per square kilometre: <10,0; 10,0-24,9; 2549.9; 50-99,9; 100-249,9; 245-499,9; 500-999,9; ≥1000) Low, …, high (<250, 250-449, 450-549, 550-749; ≥750 employed persons/1000 habitants) : : Under 2, 2-6, 6-11, 11-15, 15-20, 20-26, … , 65+ Male, female [no women/men, …, uni sexe, only women/men] Black, White, Asian, Hispanic, Arabic, … British, French, German, Swiss, Italian, Spanish, Turkish, Polish, Swedish, … Catholic, Protestant, Jewish, Muslim, Hindu, Buddhist, other, none Baby boomers; Generation Xers (68ers, 70ers, 80ers, 90ers), … Worker, sales, clerical, officials & proprietors, professional & technical, managers,... In education (school, university), full-time/part-time work, housewife, unemployed,… [Young, single], [young, married, no children], [young, married, youngest child under 6], [older, married, children], [older, married, adult children], [older, single], … 1, 2, 3, 4, 5 and more Grade school or less, high school, … , college graduate (low vs. high educated) Lower lowers, upper lowers, working, middle, upper middle, lower uppers, upper uppers Household income, number of persons in the household with own income, household income per capita, personal net income, disposable income, ... ; ; ; ; ; ; : : : : : : : ; ; ; ; ; ; Culture-oriented, sports-oriented, outdoor-oriented, etc. Compulsive, gregarious, authoritarian, ambitious, etc. Lower, middle, higher social status Traditional (duty, order), modern (Individualisation, self-realisation, hedonism, pleasure) and pro-active change (patchwork, virtual society, multi-options); Frugal traditional, materialistic workers, traditional commoner, status oriented, well established, post-materialist, new middle class, escapists, experimentalists, modern performer Being vs. possessions Peace and personal security vs. living ones’ own emotions Secure world, steady world, standing world, authentic world, new world, cosy tech world, crafty world, magic world Regular occasion, special occasion Quality, service, economy or speed Very low, …, very high price sensibility or consciousness Very low, …, very high demand for service Very low, …, very high brand awareness or brand identity Very low, …, very high demand for quality Very low, …, very high involvement ; ; ; ; ; ; : ; ; ; ; ; ; ; Types of buying decisions Processes, e.g. Extensive Limited Routine Impulsive User status Usage rate Readiness stage Attitude Adoption time Loyalty status High price, rarely purchased, careful evaluation and choice Medium price, moderate information demand Low price, frequently purchased, few alternatives Response to an intensive stimuli, no evaluation of alternatives Non user, ex-user, potential user, first time user, regular user Very light user, light user, medium user, heavy user, very heavy user Unaware, aware, informed, interested, desirous, intending to buy Hostile, very negative, negative, indifferent, positive, very positive, enthusiastic Innovators, early adopters, early majority, late majority, laggards None, very low, medium, strong, very strong, absolute ; ; ; ; ; ; ; ; ; ; Source: following [Kotler et al. 2005, p. 399] :: Fuzzy classification not adequate ;: Fuzzy classification with discrete or ;: continuous membership functions possible 141 Appendix Appendix 6: Attributes, Classes, Terms, Domains and Contexts of Credit Rating Attribute (Aijkl) & hierarchy level Li 1 2 3 4 Membership functions (μ) Classes C1) creditworthy C2) personally not creditworthy C3) materially not creditworthy Family situation (A311) Employment (A312) Personal creditworthiness (A21) C1-1) personally creditworthy C1-2) job circumstances not creditworthy C1-3) family circumstances not creditworthy C1-4) personally not creditworthy μpers. creditworthy + μmat. creditworthy μpers. not creditworthy + μmat. creditworthy μpers. creditworthy + μmat. not creditworthy μpers. not creditworthy + μmat. nicht kw not creditworthy creditworthy μfamily c. creditworthy + μjob c. creditworthy μfamily c. creditworthy + μjob c. not creditworthy μfamily c. not creditworthy + μjob c. creditworthy μfamily c. not creditworthy + μjob c. not creditworthy Number of children (A4114) Age of children (A4115) Profession (A4121) Qualification (A4122) Employer (A4123) Duration of employment(A4124) Income (A321) μearning c. creditworthy + μexpenses c. creditworthy μearning c. creditworthy + μexpenses c.not creditworthy μearning c. not creditworthy + μexpenses c. creditworthy μearning c. not creditworthy + μexpenses c. not creditworthy Outgoings (A322) Rent, mortgage rate (A4221) Alimonies (A4222) Financial obligations (A4223) Reason for credit (A4224) other (A4225) c Legend: scores assigned to values of : continuous ( discrete: {very bad, bad, insufficient} cont.: [0,99]; (50100) discrete: {sufficient, good, excellent} [0, 100]; (0,50) Family status (A4113) other (A4215) cont.: [0,99]; (0,49.9) [0, 49]; (0, 24.9) personally creditworthy Civil status (A4112) Account information (A4214) Context K(Aijkl) s/d Family situation not creditworthy Family situation creditworthy 18, ..., 100 single, married, divorced, separated, widowed single, single mother, concubinage, married 0, 1, 2, 4, >4 0, ... , 30 years Employment not creditworthy Employment creditworthy [low, … , high qualified] [labour contract, <1, >1, >3 years] - Net income (A4211) Property (A4212) Loan securities (A4213) continuous : [0,200]; (0,100) d discrete : {very bad, bad, insufficient, sufficient, good, excellent} personally not creditworthy Age (A4111) C2-1) materially creditworthy C2-2) Expenses circumstances not creditwort. C2-3) Earning capacity not creditworthy C2-4) materially not creditworthy Scores S(Aijkl) [scores],(%) c other (A4125) Material creditworthiness (A22) Overall creditworthiness (A1) C4) not creditworthy Terms T(Aijkl) [50, 100]; (25, 50) s/d [25, 50]; (12.5, 25) d [0, 10]; (0, 5) s [0, 10]; (0, 5) d [0, 10]; (0, 5) s [0, 10]; (0, 5) d [0, 10]; (0, 5) s/d Income not creditworthy Income creditworthy [0, ≥ 10'000] [0, ≥ 1'000'000] [very low, ... , very high] [High, …, low negative; low, ..., very high] Outgoings not creditworthy Outgoings creditworthy [very low, … , very high] [very high, ... , none] [very high, ... , none] [un-, ... , important] d [0, 24]; (0, 12.49) [0, 50]; (0, 25) [25, 50]; (12.5, 25) d [0, 10]; (0, 5) d [0, 10]; (0, 5) d [0, 10]; (0, 5) s/d [0, 10]; (0, 5) s/d [0, 10]; (0, 5) Materially not creditworthy Materially creditworthy [0, 24]; (0, 12.49) [0, 50]; (0, 25) [0, 49]; (0, 24.9) [0, 100]; (0, s/d 50) [50, 100]; (25, 50) s/d [0, 24]; (0, 12.49) [0, 50]; (0, 25) [25, 50]; (12.5, 25) s/d [0, 10]; (0, 5) s/d [0, 10]; (0, 5) s/d [0, 10]; (0, 5) s/d [0, 10]; (0, 5) s/d [0, 10]; (0, 5) d [0, 24]; (0, 12.49) [0, 50]; (0, 25) [25, 50]; (12.5, 25) s/d [0, 10]; (0, 5) s/d [0, 10]; (0, 5) s/d [0, 10]; (0, 5) s/d [0, 10]; (0, 5) s/d [0, 10]; (0, 5) ) or : discrete membership functions ( ); 142 s/d : both possible Appendix So eine Arbeit wird eigentlich nie fertig, man muss sie für fertig erklären, wenn man nach Zeit und Umständen das Mögliche getan hat. Johann Wolfgang von Goethe 143 Statement FACULTE DES SCIENCES ECONOMIQUES ET SOCIALES / WIRTSCHAFTS- UND SOZIALWISSENSCHAFTLICHE FAKULTÄT DEKANAT BD. DE PÉROLLES 90 1700 FRIBOURG ERKLÄRUNG Ich versichere, dass ich die vorstehende Arbeit selbständig angefertigt und entsprechend den Grundsätzen wissenschaftlicher Ehrlichkeit abgefasst habe. Es ist mir bekannt, dass andernfalls die Abteilung gemäss dem Abteilungsbeschluss vom 28.11.1984 das Recht hat, den auf Grund dieser Arbeit verliehenen Titel zu entziehen. Fribourg, den 7. März 2007 ............................................ Darius Zumstein - 144 -