An Exploratory Look at Supermarket Shopping Paths
Statistics and Probability
We present analyses of an extraordinary new dataset that reveals the path taken by individual shoppers in an actual grocery store, as provided by RFID (radio frequency identification) tags located on their shopping carts. The analysis is performed using a multivariate clustering algorithm not yet seen in the marketing literature that is able to handle data sets with unique (and numerous) spatial constraints. This allows us to take into account physical impediments (such as the location of aisles and other inaccessible areas of the store) to ensure that we only deal with feasible paths. We also recognize that time spent in the store plays an important role, leading to different cluster configurations for short, medium, and long trips. The resulting three sets of clusters identify a total of 14 "canonical path types" that are typical of grocery store travel, and we carefully describe (and cross-validate) each set of clusters These results dispel certain myths about shopper travel behavior that common intuition perpetuates, including behavior related to aisles, end-cap displays, and the "racetrack." We briefly relate these results to previous research (using much more limited datasets) covering travel behavior in retails stores and other related settings.