We invited “residents” of a virtual world who vary in real-world age and occupation to play a trust game with stakes comparable to “in world” wages. In different treatments, the lab wall was adorned with an emotively suggestive photograph, a suggestive text was added to the instructions,...

The sanctioning of norm-violating behavior by an effective formal authority is an efficient solution for social dilemmas. It is in the self-interest of voters and is often favorably contrasted with letting citizens take punishment into their own hands. Allowing informal sanctions, by contrast,...

Entrusting the power to punish to a central authority is a hallmark of civilization. We study a collective action dilemma in which self-interest should produce a sub-optimal outcome absent sanctions for non-cooperation. We then test experimentally whether subjects make the theoretically optimal...

We present results from a novel experiment on the effect of a policy designed to encourage cooperation in a prisoner's dilemma game. We find that the effect of this policy on the level of cooperation is greater when it was chosen democratically by the subjects than when it was exogenously...