The Desirability Bias Beyond Dichotomous Outcomes

Wishful thinking refers to the increased likelihood of predicting an outcome due to a preference for that outcome. Research exploring wishful thinking has been limited to dichotomous decisions even though many decisions involve more than two outcomes. This study asked participants to make predictions about upcoming events. Specifically, they were shown a multicolor grid of squares and were asked to predict which color they thought the computer would pick at random. Preference for one color versus the other was manipulated using desirable and undesirable point information. Importantly, half of the participants made predictions when there were two possible outcomes (i.e., two different colors of squares in each grid) while the other half made predictions when there were four possible outcomes (i.e., four different square colors). Overall, participants were more likely to predict desirable outcomes over undesirable outcomes—that is, they exhibited wishful thinking. Furthermore, participants were as likely to make wishful predictions when there were two possible outcomes versus when there were four possible outcomes, meaning that wishful thinking did not change as a function of the number of outcomes. This finding extends previous wishful thinking findings by generalizing the results to situations where there are more than two outcomes.