We compare how children aged 9-12 in Colombia and Sweden cooperate in a Prisoner's Dilemma. We introduce a new measurement device for cooperation that can be easily understood by children. There is some evidence of more cooperation in Sweden than in Colombia. Girls in Colombia are less...

We compare how children aged 9-12 in Colombia and Sweden cooperate in a Prisoner's Dilemma. We introduce a new measurement device for cooperation that can be easily understood by children. There is some evidence of more cooperation in Sweden than in Colombia. Girls in Colombia are less...

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...

We study the stability of voluntary cooperation in response to varying group growth rates. Using a laboratory public-good game, we construct a situation where increasing group size yields potential efficiency gains, but only with sustained cooperation. We then study the effect of exogenously...

We study the stability of voluntary cooperation in response to varying group growth rates. Using a laboratory public-good game, we construct a situation where increasing group size yields potential efficiency gains, but only with sustained cooperation. We then study the effect of exogenously...

We study the stability of voluntary cooperation in response to varying rates at which a group grows. Using a laboratory public-good game with voluntary contributions and economies of scale, we construct a situation in which expanding a group's size yields potential efficiency gains, but only if...