Option similarity modulates subjective strategy use and the value of unchosen options

Poster Session D - Monday, April 15, 2024, 8:00 – 10:00 am EDT, Sheraton Hall ABC

Azara Lalla¹ (azara.lalla@mail.mcgill.ca), Caitlin Maloney¹, Signy Sheldon¹; ¹McGill University

Studies have shown that the outcome of a choice updates the value of the chosen option. Less studied is how this outcome affects the value of the unchosen option, for which two predictions exist: first, the outcome associated with the chosen option may generalize to the unchosen option and, second, the outcome of the chosen option may inversely update the value of the unchosen option. We tested these predictions under two choice conditions using a behavioral experiment. Participants made choices between conceptually similar (similar condition: brownie, cupcake) and conceptually dissimilar options (dissimilar condition: cookie, salad), providing written justifications for their choices that were analyzed for objective and subjective strategy use. Next, participants learned whether the outcome of their choice was rewarded or unrewarded. Finally, they made novel choices between two previously unchosen options from either the similar or dissimilar condition, in which one member of the pair was associated with a rewarded choice and the other with an unrewarded choice. Results show that participants used more subjective and less objective strategies in the similar than dissimilar condition. Participants learned the outcome of their choices equally across conditions, but in the similar condition were significantly less likely than chance (41%) to select unchosen options that were associated with a rewarded outcome. Interestingly, regardless of condition, we found that participants who provided more objective justifications for their decisions showed a larger inverse decision bias. These findings add to a growing body of work investigating the effects of option similarity on value-based decision-making.

Topic Area: THINKING: Decision making