Cognitive reflection predicts the acceptance of unfair ultimatum game offers

In the ultimatum game, one player proposes a split of money between him- or herself and another player, who can accept the offer (and both players keep the allocated money) or reject the offer (and both players get nothing). The present study examined predictors of accepting unfair ultimatum offers. In Study 1, 184 participants responded to an unfair ultimatum offer, completed a measure of cognitive reflection, and completed a self-report measure of rational and experiential thinking. Slightly more than half of the participants (54.3%) accepted the unfair offer, and cognitive reflection was positively correlated with accepting unfair offers. The rational and experiential thinking scales were not significantly correlated with ultimatum decisions. In Study 2, 306 participants responded to 20 ultimatum offers that varied in fairness and completed an expanded measure of cognitive reflection. Performance on the cognitive reflection measure predicted the number of ultimatum offers accepted. These results suggest that rejecting ultimatum offers is related to intuitive, heuristic-based thinking, whereas accepting offers is related to deliberate, analytic-based thinking