Tracking the eye of the beholder: The roles of effort and preferences in everyday decision making

Abstract: This study investigates the relation between preferences and cognitive effort in decision making tasks in a natural setting. Does the way a supermarket’s shelves are organized affect how easy it is to choose what items to purchase? Does it affect the quality of our choice? The eye-movements of participants were recorded during their regular shopping trips in two supermarkets with different shelf organizations. They also responded to surveys about their shopping routines and product preferences. In the analysis, the participants were divided into groups according to their stated product preferences: one group who strongly favored certain sub-categories of products (e.g. ecological pasta); one group who strongly favored certain brands and one control group who had no strong preference either way. This division meant that each of the first two groups’ preferences were either congruent or incongruent with the organization of the shelves in the respective supermarket. The control group was used as a base-line. Measurements of total time and evaluation time in front of each shelf; number of products looked at; number of returns to products already looked at and self-reported difficulty in choosing products were used as indicators of cognitive effort in finding and choosing products. Preferences were matched with product attributes to calculate the quality of purchase options and ultimate decision quality. The results suggest that participants used less effort in choosing their products when the shelf was organized in a way congruent with their preferences (e.g. by category for a category-focused participant). Results also indicate that congruence entails lower quality purchase decisions. That is, the attributes of the chosen products match the participant’s stated preferences poorly. It is argued that when cognitive resources are freed up because less effort is used in finding and choosing a product, those resources are not necessarily used to make better decisions. Rather, the less effort that is used throughout the whole process, the worse the purchase decisions will be.