Perceptions of self and other in the prisoner's dilemma: outcome bias and evidential reasoning.

In the prisoner's dilemma, self-interest clashes with collective interest. The way players resolve this conflict affects how others view them. Cooperators are seen as more moral than defectors, and, when there is no information about the other player's choice, cooperators and defectors are seen as equally competent. However, players who are defected against are seen as less competent, especially if they themselves cooperated (Experiments 1 and 2). Similarly, cooperators see themselves as more moral, but not as less competent, than defectors do (Experiments 3). Independent of concerns about reputation and self-image maintenance, evidential reasoning contributes to cooperative behavior. Players who project their own attitudes onto others are more likely to cooperate (Experiments 3). Compared with classic game theory, a theory of reputational concerns and evidential reasoning is better equipped to explain empirical patterns of choice behavior in social dilemmas.