While there is ample evidence of a society-wide cooperation norm, it is not as clear who upholds this norm. In the present paper, we investigate whether there are gender differences with respect to norm enforcement. We let 1403 subjects play games of punishment and reward, individually or in...

This paper compares cooperation among Columbian and Swedish children aged 9-12. We illustrate the dynamics of the prisoner’s dilemma in a new task that is easily understood by children and performed during a physical education class. We find some evidence that children cooperate more in Sweden...