The influence of partner presence on cooperation and norm formation

Abstract Previous studies have shown that the presence of others makes people more norm-compliant and behave more cooperatively in economic games. As important others who have interdependent relationship with the individual, the influence of the presence of partners on individual’s behavior has been overlooked. In this study, we used the repeated public goods game to examine how the presence of partners affects individual’s cooperative behavior and group’s norm formation in both no-punishment and punishment situations among 42 groups of four anonymous players (N = 168). The results of Generalized Estimating Equations showed that in the absence of punishment, the presence of partners significantly improved participants’ average level of cooperation but did not promote the formation of group norms, whereas when punishment was available, partner presence changed the way punishment being administered and in turn strengthened group norms and encouraged more consistent cooperative behavior. The effects of mere partner presence and its interaction with punishment on cooperation and norm formation were discussed.