We show in a public goods experiment on three continents that conditional cooperation is a universal behavioral regularity. Yet, the number of conditional cooperators and the extent of conditional cooperation are much higher in the United States than anywhere else.

We examine gender differences in trust in another party's cooperation (CC) or its ability (AC). While men and women do not differ concerning trust in cooperation, gender has a strong influence when trust in another subject's ability is required.

Arad and Rubinstein (2012a) have designed a novel game to study level-k reasoning experimentally. Just like them, we find that the depth of reasoning is very limited and clearly different from that in equilibrium play. We show that such behavior is even robust to repetitions; hence there is, at...

In an experiment, we study risk-taking of cohabitating student couples, finding that couples’ decisions are closer to risk-neutrality than single partners’ decisions. This finding is similar to earlier experiments with randomly assigned groups, corroborating external validity of earlier results.

We study the effects of voluntary leadership in experimental public goods games when each group member can volunteer to contribute before the other members. We find that voluntary leadership increases contributions significantly, compared to a treatment where leadership is enforced exogenously.

We examine social preferences of Swedish and Austrian children and adolescents using the experimental design of Charness and Rabin (2002). We find that difference aversion decreases while social-welfare preferences increase with age.