Deliberately ignoring unfairness: Responses to uncertain inequality in the Ultimatum Game

Why do people punish experienced unfairness if it induces costs for both the punisher and punished person(s) without any direct material benefits for the punisher? Economic theories of fairness propose that punishers experience disutility from disadvantageous inequality and punish in order to establish equality in outcomes. We tested these theories in a modified Ultimatum Game (N = 1,370) by examining whether people avoid the urge to reject unfair offers, and thereby punish the proposer, by deliberately blinding themselves to unfairness. We found that 53% of participants deliberately ignored whether they had received an unfair offer. Among these participants, only 6% of unfair offers were rejected. In contrast, participants who actively sought information rejected 39% of unfair offers. Averaging these rejection rates to 21%, no significant difference to the rejection rate by participants who were directly informed about unfairness was found--in line with economic theories of fairness. We interpret these findings as evidence for sorting behavior: People who want to punish experienced unfairness seek information about it, while those who are unwilling to punish deliberately ignore it.