In finitely repeated prisoner dilemma games, two-person teams start out with significantly less cooperation than individuals, consistent with results reported in the social psychology literature. However, safety concerns quickly give way to teams cooperating significantly more than individuals....

The unique Nash equilibrium of the finitely repeated n-person Prisoners' Dilemma calls for defection in all rounds. One way to enforce cooperation in groups is ostracism: players who defect are expelled. If the group's members prefer not to diminish its size, ostracism hurts the legitimate...

We explore the relationship between individuals' disposition to cooperate and their inclination to engage in peer punishment as well as their relative importance for mitigating social dilemmas. Using a novel strategy-method approach we identify individual punishment patterns and link them with...