Implicit Reputation Cues and Strong Reciprocity

Evolutionary psychologists argue that strong reciprocity is primarily shaped by an evolutionary history of repeated interactions in which it was in the self-interest of people to reciprocate favors. For this reason modern humans are hypothesized to respond to variations in all kinds of subtle reputational cues such as human voices in the environment, whether actions take place in the dark or during daylight, i.e, by cues that induce feelings of being observed. These variations in reputational cues are predicted to affect reciprocal behavior even if they are not associated with any changes in pecuniary incentives. We address this hypothesis by implementing an implicit reputation treatment in which trustees in a trust game are “observed” by eyes on their computer screen which are thought to activate emotional programs of prosocial behavior. In order to assess the relative importance of potential reciprocity-enhancing effects of implicit reputational cues we compare this treatment with a treatment in which trustees have a pecuniary incentive to behave nicely because the future trustors are informed about the trustees past actions. We find no support for the evolutionary psychology hypothesis because implicit reputation cues have no effect on trustee behavior while explicit pecuniary reputation incentives cause large increase in trustees’ back transfers.