A model to optimize rack layout in a retail store

The physical layout of a retail store is known to influence the attitude and behavior of shoppers and affect store performance. An important role of the store's layout is to expose shoppers to merchandise in order to facilitate consideration and ultimately purchasing of exposed products. This work focuses on determining which rack layouts maximize exposure of products to a shopper. To do this, we introduce the retail rack layout problem (RRLP), which identifies the optimal single or multi-column rack orientations in a constrained space in order to maximize exposure to the shopper. To solve this problem, we propose a mixed-integer, non-linear optimization model, which we solve using a particle swarm optimization (PSO) algorithm. Results indicate that an increase of exposure ranging from 213-226% (small head turns) and 17-18% (large head turns) over 90°-rack layouts can be achieved with angled-racks (acute or obtuse from a shopper's travel path) depending on the duration of exposure. The increase in exposure comes at the expense of loss of display space and is sensitive to the shopper's field of regard (angular limit and depth of vision). We also show that multiple competitive layout designs with 1-, 2-, and even 3-columns may exist for a given system configuration that offer similar exposure values.