The online store was situated in an experimental laboratory
in a university. Each participant was provided with a dedicated
computer terminal to shop during the visit to the store. The
store stocked 89 stock keeping units (SKUs) in nine product
categories (see Web Appendix 1), which remained unchanged
throughout the experiment. These categories and SKUs were
picked based on screening responses, being commonly purchased
items. Detailed pricing data from a local grocery chain,
both for online and offline stores, was collected for several
months preceding the study. We used these data to calculate
the average price and price changes for each of the SKUs.