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...

Prior research demonstrates a willingness to incur costs to punish norm violators. But, how strong are the motives underlying such acts? Will people rely on "excuses" to avoid acting on costly punishment intentions, as with other costly pro-social acts? In a laboratory experiment, we find that...

Institutions are an important means for fostering prosocial behaviors, but in many contexts their scope is limited and they govern only a subset of all socially desirable acts. We use a laboratory experiment to study how the presence and nature of an institution that enforces prosocial behavior...

Institutions are an important means for fostering prosocial behaviors, but in many contexts their scope is limited and they govern only a subset of all socially desirable acts. We use a laboratory experiment to study how the presence and nature of an institution that enforces prosocial behavior...