Voters in democracies can learn from the experience of neighbouring states: about policy in a direct democracy ("policy experimentation"), about the quality of their politicians in a representative democracy ("yardstick competition"). Learning between states creates spillovers from policy...

In an online survey, the honesty of residents of eight countries was measured in three ways: by the standard coin flip experimental paradigm, by a new experiment designed to resemble a test with the possibility of cheating, and by a questionnaire of integrity. While the coin flip paradigm...

Human societies of all kinds solve a problem of order. That is what differentiates them from sets of isolated individuals. The problem may be solved in various ways: in particular, some societies possess a state which provides order, while others are stateless. However, the existence of a state...

Previous work has found that in social dilemmas, the selfish always free-ride, while others will cooperate if they expect their peers to do so as well. Outcomes may thus depend on conditional cooperators’ beliefs about the number of selfish types. An early round of the game may be played...

Costly signalling of commitment to a group has been proposed as an explanation for participation in religion and ritual. But if the signal’s cost is too small, freeriders will send the signal and behave selfishly later. Effective signalling may then be prohibitively costly. If the average...

Field studies of conflict report cycles of mutual revenge between groups, often linked to perceptions of intergroup injustice. We test the hypothesis that people are predisposed to reciprocate against groups. In a laboratory experiment, subjects who were harmed by a partner’s uncooperative...