Shadowing of Grocery Shoppers and Appropriate Classification
Transcrição
Shadowing of Grocery Shoppers and Appropriate Classification
AG DANK München, 22. November 2014 23.12.2014 Shadowing of Grocery Shoppers and Appropriate Classification schemes Udo Wagner University of Vienna Herbsttagung der Arbeitsgruppe Datenanalyse und nummerische Klassifikation 22. November 2014 Agenda • Introduction • Conceptual Considerations • Design of Empirical Study • Data Analysis • Conclusions Wagner, U., Ebster, C., Eske, U. und Weitzl, W. (2014): „The Influence of Shopping Carts on Customer Behavior in Grocery Store“, in: Marketing, ZFP – Journal of Research and Management , 36(3), S. 165-175. Udo Wagner Udo Wagner, Universität Wien 1 AG DANK München, 22. November 2014 23.12.2014 Introduction • Cell phone tracking by US retailers to better compete with online retailers (controversial issue) • In-store observations are used for many decades analyze shopper orientation (Gröppel-Klein, Bartmann, 2009) identify predominant paths shoppers take inside the store (Larson, Bradlow, Fader, 2005) compare shoppers’ level of exposure to in-store visuals (Sorensen, 2003,2009) capture in-store interactions between parents and their children (Ebster, Wagner, Neumüller, 2009) measure customer traffic in different parts of a store (Newman, Yu, Oulton, 2002) analyze the effects of clockwise or anti-clockwise walking patterns in a store (Gröppel-Klein, Bartmann, 2008) Udo Wagner 3 Devices used for recording instore movement • GPS (cell phone tracking) • RFID • Automatic tracking of (specially equipped) carts (Path-Tracker®) • Video observation Udo Wagner Udo Wagner, Universität Wien 4 2 AG DANK München, 22. November 2014 23.12.2014 • Larson, Bradlow and Fader (2004) - Path-Tracker® = electronic observation / tracking system - Typical shopper movements are recorded and analyzed - Prototypical shopping paths - „k-medoids clustering algorithm“: Clustering of customers according to time spent in the store • low (2 – 10 Minutes) • medium (10 – 17 Minutes) • high (more than 17 Minutes) → → → 2 medoids 4 medoids 8 medoids Udo Wagner 5 Customers‘ interaction with shopping carts RQ1: What is the effect of parking shopping carts on the relationship between in-store movement and purchase behavior? RQ2: Does store design moderate these relationships? Grocery stores (utilitarian goods), exploratory study, unobtrusive (human) observation procedure Udo Wagner Udo Wagner, Universität Wien 6 3 AG DANK München, 22. November 2014 23.12.2014 Conceptual considerations Shopping carts facilitate shopping + temporarily store products before purchasing + deposit personal belongings + allow to touch merchandise Shopping carts might hinder shopping - restricted movement in the store - reduced walking speed - reduced flexibility of walking direction Shopping cart behavior might be moderated by • time pressure of customers • number of shoppers present in the store • perceived crowding • fear of pickpockets • environmental characteristics of store • time of the day, season • familiarity with the store Udo Wagner Effects of crowding (many shoppers are present) can operate in opposite directions: + individual space becomes limited parking carts helps regain mobility leaving the cart unattended might prove risky (especially when personal belongings are stored in the cart) parked carts of other shoppers might be perceived negatively (butt-brush effect) 7 Conceptual considerations parking carts behavior store design (a‘) (b‘) (c‘) (c) (b) in-store movement behavior purchase behavior (a) Simplified model: 1. Parking shopping carts is considered as a mediating construct that influences the relationship between in-store movement and purchase behavior 2. Store design is considered as a moderator Udo Wagner Udo Wagner, Universität Wien 8 4 AG DANK München, 22. November 2014 23.12.2014 Conceptual considerations parking carts behavior store design (a‘) (b‘) (c‘) (c) (b) in-store movement behavior purchase behavior (a) RQ1: What is the effect of parking shopping carts on the relationship between in-store movement and purchase behavior? (a) Patrons who spend more time in a store will purchase more often (b) Patrons who spend more time in a store are more likely to park their carts more often (c) Patrons who park their carts more often will purchase more often 9 Udo Wagner Conceptual considerations parking carts behavior store design (a‘) (b‘) (c‘) (c) (b) in-store movement behavior purchase behavior (a) RQ2: Does store design moderate these relationships? (a’) The relationship between the time required for shopping and the number of purchases is less well established for a modern, conveniently designed, store (i.e., shopping experience is more pleasant in a modern store) (b’) The relationship between the time required for shopping and the frequency of parking the carts is stronger for a modern, conveniently designed, store (i.e., perceived crowding is less established in a modern store, thus customers are more willing to park their carts) (c’) The relationship between the frequency of parking the carts and the number of purchases is stronger for a modern, conveniently designed, store (i.e., a modern design facilitates in-store navigation, customers feel more comfortable and tend to make more unplanned purchases) Udo Wagner Udo Wagner, Universität Wien 10 5 AG DANK München, 22. November 2014 23.12.2014 Design of Empirical Study: Disguised observation method Two observers followed selected shoppers covertly and recorded their shopping paths on a tablet computer with a shadowing tool (plotting individual shopping paths on digitized shopping floor plan in real time) Demonstrationsvideo Udo Wagner 11 Design of Empirical Study: Floor plan of traditional store • • • • • two large supermarkets belong to the same grocery retail chain carry about the same assortment of products have approximately the same size of total sales located in different parts of the same city Meat & sausages Check-out area Long aisles, rectangular arranged shelves Frozen food & dairy products Fruits & vegetables Udo Wagner Udo Wagner Udo Wagner, Universität Wien 12 6 AG DANK München, 22. November 2014 23.12.2014 Design of Empirical Study: Floor plan of modern store • • • three weeks observation period five well trained observers / interviewers randomized selection of (single) shoppers Frozen food & dairy products Check-out area landmarks, spacious aisles, shelves arranged in freeflowing patterns, lower heights of the shelves Meat & sausages Fruits & vegetables Udo Wagner Udo Wagner 13 Design of Empirical Study Collected data 197 shoppers in the traditional store 209 in the modern store By means of observation: • in-store shopping path data (with and without carts) • purchases (with and without carts) • frequency, places and duration of parked carts • walking speed • shopping duration • calendar date, time of day • handbags carried in the cart • gender, age By means of communication (only for some of persons of the sample): • weekly shopping behavior, • perceived store atmospherics • functionality of cart (only 7% indicated that they noticed someone was following them through the store) Udo Wagner Udo Wagner, Universität Wien 14 7 AG DANK München, 22. November 2014 23.12.2014 Data analysis: descriptives Open checkout cashiers Type of store Women <40 40‐60 >60 range mode traditional 65% 34% 42% 24% 3‐9 5 modern 66% 39% 39% 22% 2‐10 4 Shops are fairly similar in terms of customer gender and age, average time spent in the store, using carts for carrying personal belonging (66%) 15 Udo Wagner Data analysis: descriptives Parking shopping carts n Average number of purchases Time spent shopping without at least once on average with total shopping cart traditional 197 19 min 54% 1.64 8.51 1.13 7.38 modern 209 21 min 74% 2.82 10.72 2.39 8.33 z, t‐Test ‐2.07 ‐4.19 ‐4.21 ‐4.04 ‐4.18 ‐2.01 p‐level .04 <.01 <.01 <.01 <.01 .04 Different variance of time spent in the store, different patterns of parking carts, different number of products purchases (in total and with/without cart) Udo Wagner Udo Wagner, Universität Wien 16 8 AG DANK München, 22. November 2014 23.12.2014 Data analysis: measurement parking carts behavior store design (a‘) (b‘) (c‘) (c) (b) in-store movement behavior purchase behavior (a) STt: in-store movement behavior surplus of time customer spent in the store (given personal demographics and demand) CPt: cart parking behavior frequency of parking carts during a shopping trip PPt: purchase behavior number of products purchased DEt: store design binary (traditional / modern) 17 Udo Wagner Data analysis: research questions DEt store design CPt (a‘) parking carts behavior (b‘) (c‘) (c) (b) STt in-store movement behavior purchase behavior (a) CPt α1 PPt γ1 STt error1t PPt 2 2 CPt 2 STt error2t with: 1,2 , 2 ,1, 2 parameters Udo Wagner Udo Wagner, Universität Wien 18 9 AG DANK München, 22. November 2014 23.12.2014 γ1 STt error1t CPt α1 PPt 2 2 CPt 2 STt error2t Data analysis: research questions with : 1 , 2 , 2 , 1 , 2 Traditional store Modern store n=197 n=209 parameters Equation 1: Surplus of time ( ˆ1 ) Frequency of parking carts * R2=.11 ˆ1 p ˆ1 p .33 <.01 .40 <.01 F=24.17 <.01 F=38.86 <.01 R2=.16 Equation 2: ˆ2 ), frequency of parking carts ( ) ̂ 2 Surplus of time ( Number of purchases * R2=.45 * ˆ2 p ̂ 2 p .59 <.01 .17 <.01 F=79.29 <.01 R2=.44 ˆ2 p ̂ 2 p .49 <.01 .30 <.01 F=81.41 <.01 Only standardized regression coefficients are reported. All parameter estimates are plausible and statistically significant, fit of the model is satisfactory 19 Udo Wagner γ1 STt error1t CPt α1 Data analysis: research questions PPt 2 2 CPt 2 STt error2t with : 1 , 2 , 2 , 1 , 2 parameters RQ1: What is the effect of parking shopping carts on the relationship between in-store movement and purchase behavior? Mediation test on (Sobel 1982; Iacobucci 2012): traditional modern zMediation 2.64 p .01 zMediation 3.99 p .01 Frequency of parking shopping carts partially mediates the relationship between surplus of time and number of purchases √ RQ2: Does store design moderate these relationships? (a’) The relationship between the time required for shopping and the number of purchases is less well established for a modern, conveniently designed, store √ (b’) The relationship between the time required for shopping and the frequency of parking the carts is stronger for a modern, conveniently designed, store √ (c’) The relationship between the frequency of parking the carts and the number of purchases is stronger for a modern, conveniently designed, store √ By utilizing the dummy variable DEt we estimate our model for both types of stores simultaneously and find a significant moderator effect in all three cases Udo Wagner Udo Wagner, Universität Wien 20 10 AG DANK München, 22. November 2014 23.12.2014 Data analysis: effect of personal belongings carried in the cart – RQ1 Traditional store Only customers without belongings kept in carts are considered n=70 R2=.02 n=69 p ˆ1 p .14 .24 .59 <.01 F=1.41 .24 F=35.84 <.01 R2=.35 R2=.45 2 p ̂ 2 p .64 <.01 .12 .19 F=27.32 <.01 R2=.44 ˆ2 p ̂ 2 p .51 <.01 .22 .06 F=26.01 <.01 Mediation test, with Only customers with belongings kept in carts are considered n=127 n=140 Equation 1: Surplus of time ( ˆ ) Frequency of parking carts * ˆ1 R2=.15 1 ˆ1 p .39 <.01 F=21.87 <.01 R2=.10 p .32 <.01 F=15.55 <.01 Equation 2: Surplus of time ( ˆ ), frequency of parking carts ( ) ̂ Number of purchases * R2=.45 * 2 ˆ2 p .56 <.01 F=50.06 <.01 parameters Mediation test, without Equation 2: Surplus of time (ˆ2), frequency of parking carts ( ) ̂ Number of purchases * ˆ2 with : All parameter estimates are plausible and most of them statistically significant, fit of the model is satisfactory (with but one exception) Equation 1: ˆ1) Frequency of parking carts * Surplus of time ( ˆ1 PPt 2 2 CPt 2 STt error2t 1 , 2 , 2 , 1 , 2 Modern store γ1 STt error1t CPt α1 ̂ 2 .21 2 p ˆ2 p ̂ 2 p <.01 .50 <.01 .32 <.01 F=55.20 <.01 R2=.45 Frequency of parking shopping carts partially mediates the relationship between surplus of time and number of purchases even when potential influence of belongings kept in carts is considered √ Only standardized regression coefficients are reported. 21 Udo Wagner Data analysis: effect of personal belongings carried in the cart – RQ2 Modern store Traditional store without with Surplus of time ( ) Frequency of parking carts without with Surplus of time ( ) Number of purchases Udo Wagner Udo Wagner, Universität Wien without with Frequency of parking carts ( ) Number of purchases 22 11 AG DANK München, 22. November 2014 23.12.2014 Data analysis: effect of personal belongings carried in the cart – RQ2 CPt α1 γ1 STt error1t PPt 2 2 CPt 2 STt error2t √ with : 1 , 2 , 2 , 1 , 2 (a’) parameters is dominant and larger for the traditional store for the modern store, no influence of belongings kept in cart (b’) for both conditions (c’) for “without” condition Interaction effects between store design and belongings kept in cart: behavior appears more similar in the two stores if belongings are in cart (due to fear of pickpockets?) RQ2: Does store design moderate these relationships? (a’) The relationship between the time required for shopping and the number of purchases is less well established for a modern, conveniently designed, store (b’) The relationship between the time required for shopping and the frequency of parking the carts is stronger for a modern, conveniently designed, store (c’) The relationship between the frequency of parking the carts and the number of purchases is stronger for a modern, conveniently designed, store Udo Wagner 23 Data analysis: Typical patterns of shopping paths – traditional store Udo Wagner Udo Wagner, Universität Wien 24 12 AG DANK München, 22. November 2014 23.12.2014 Data analysis: Typical patterns of shopping paths – modern store Udo Wagner 25 Data analysis: Typical patterns of shopping paths, both stores Time spent in the store Patterns observed <5 minutes goal‐oriented movement; targeted areas visited 5–10 minutes movement along main aisles; targeted areas visited 10–25 minutes movement along main aisles with short side trips to secondary aisles 25–45 minutes movement along main aisles, some secondary aisles are walked through completely, center of the store is visited >45 minutes strolling through the whole sales area, longer visits in the center of the store Udo Wagner Udo Wagner, Universität Wien 26 13 AG DANK München, 22. November 2014 23.12.2014 Data analysis: typical shopping paths Modern store Traditional store 27 Udo Wagner Data analysis: typical shopping paths many few Modern store Traditional store Udo Wagner Udo Wagner, Universität Wien 28 14 AG DANK München, 22. November 2014 23.12.2014 Data analysis: walking speed Traditional store Modern store 29 Udo Wagner Data analysis: frequently used typical shopping paths without carts Modern store Traditional store Udo Wagner Udo Wagner, Universität Wien 30 15 AG DANK München, 22. November 2014 23.12.2014 Data analysis: locations for parking carts Traditional store Modern store 31 Udo Wagner Data analysis: duration for parking carts Traditional store Modern store Udo Wagner Udo Wagner, Universität Wien 32 16 AG DANK München, 22. November 2014 23.12.2014 Data analysis: total number of purchases Traditional store Modern store 33 Udo Wagner Data analysis: number of purchases without cart Traditional store Modern store Udo Wagner Udo Wagner, Universität Wien 34 17 AG DANK München, 22. November 2014 23.12.2014 Data analysis: findings on individual sales departments (rather similar across stores) Sales department Frequency of patrons’ visits Frequency of parked Duration of parking carts carts Frequency of purchases Time spent by patrons Patrons’ walking speed Fruits & vegetables high high Frozen food & dairy products long many long slow high high short many long slow Meat & sausages high high long many medium moderate Vinery low low short few long slow Pet food low low short few long slow New product offers low low short few long slow Kitchenware low low * short few long slow Cosmetics low low short few long slow Textiles low low short few long slow Checkout area high low short few short fast * Typically, customers walk around in this area without their shopping cart. Udo Wagner 35 Data analysis: general findings • Patterns do not depend substantially on type of store • High frequency of fruits & vegetables area (decompression zone) an frozen food & dairy products area • Shoppers move along aisles located near the walls of the store (race tracks) • Shoppers walk anti-clockwise • Many zones are frequently skipped (especially in the traditional store) • Areas in the middle commonly remain untouched (however, higher profit margins product are offered there) • Selection of aisles frequently visited depends on the total time spent in the store • Duration of parked carts is rather short (distribution is highly skewed) with exceptions (meat & sausages, fruits & vegetables) • Customers park their carts in spacious regions and stay in their proximity • Walking speed becomes faster along main aisles and near the checkout, slower in zones with a low frequency of visits Udo Wagner Udo Wagner, Universität Wien 36 18 AG DANK München, 22. November 2014 23.12.2014 Conclusions • Considerable heterogeneity across customers with respect to use of carts • Frequency of carts parked partially mediates the relationship between time spent in the store and the number of purchases • Design of store has a moderating effect Managerial implications • Provide in-door space for temporary parking of carts • Design of the store impacts cart parking behavior, parking carts might induce spontaneous purchases provide incentives for parking carts in particular in the center of the store • Retail strategies should be adapted account for differences within various sales departments Theoretical implications • Tracking shopping carts only might lead to considerable measurement problems • Proposed measurement tool requires further testing Udo Wagner 37 Limitations and further research • • • • • • Results are probably not generalizable No causal relationships have been established Familiarity with the store has not been adequately considered Preparing for shopping (e.g., by means of a shopping list) has not been considered Reasons for parking carts have not been identified Crowding effects have only been roughly considered • • • • Investigate other types of supermarkets, shopping aids (e.g., baskets) Investigate effects of cash deposits for using a cart Investigate size of shopping carts …. Udo Wagner Udo Wagner, Universität Wien 38 19 AG DANK München, 22. November 2014 23.12.2014 Quellen • • • • • • • • • • • • • • Berekoven, Ludwig (1995). Erfolgreiches Einzelhandelsmarketing: Grundlagen und Entscheidungshilfen. C. H Beck’sche Verlagsbuchhandlung, München, 2.überarbeitete Auflage. Berghaus, Nadine (2005). Eye-Tracking im stationären Einzelhandel: Eine empirische Anaylse der Wahrnehmung von Kunden am Point of Purchase. JOSEF EUL VERLAG GmbH, Köln, 1. Auflage Chandon, Pierre; Wesley J. Hutchinson and Scott H. Young. Unseen is Unsold: Assessing Visual Equity with Commercial Eye-Tracking Data. Marketing Science (2002), Perception Research Services, Inc., pp. 1 – 54. Hui, Sam K., Eric T. Bradlow and Peter S. Fader. Testing Behavioral Hypotheses Using an Integrated Model of Grocery Store Shopping Path and Purchase Behavior. Journal Kourennyi, Dimtri D. (2011). Customer Tracking through security camera video processing. 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