Are we nice(r) to nice(r) people? - An Experimental Analysis

We experimentally investigate whether individuals can reliably detect cooperators in an anonymous decision environment by allowing participants to condition their choices in an asymmetric prisoner's dilemma and a trust game (i) on their partner's donation share to a self-selected charity, and (ii) on whether their partner belongs to a group with high or low average donations (group affiliation). We find that high donators achieve a higher-than-average expected payoff by cooperating predominantly with other high donators. The group affiliation proved to be irrelevant.