People cooperate more in one-shot interactions than can be explained by standard textbook preferences. We discuss a set of non-standard preferences that can accommodate such behavior. They are social, in the sense of incorporating the payoffs of other persons; they are also norm-based, in the...

We study the effects of experimental design on male and female behavior in a dictator game. Following social identity theory we investigate how experimental procedure may affect outcome through gender priming, i.e. the activation of gender stereotypes specifying that women behave altruistically...

While there is ample evidence of a society-wide cooperation norm, it is not as clear who upholds this norm. In the present paper, we investigate whether there are gender differences with respect to norm enforcement. We let 1403 subjects play games of punishment and reward, individually or in...

Several experimental studies on altruism have found women to be more generous than men. We investigate whether observed gender gaps in generosity can be explained by experimental setting, where some settings are more conducive than others to activating gender identity and social norms. In a...