find a large and positive effect of endogenous institutional choice on the level of cooperation in comparison to … exogenously implemented institutions. This suggests that participation rights enhance cooperation in groups. With endogenous … levels of cooperation. Our results are evaluated against the predictions of social preference models. -- public goods …

We investigate how group boundaries, and the economic environment surrounding groups, affect altruistic cooperation and … harm those who defect, encouraging a norm of cooperation towards the group. Adding competition between groups causes even … stronger in-group cooperation, but also a qualitative change in punishment: punishment becomes anti-social, harming cooperative …