We report on a two-stage experiment in which i) we first elicit the social network within a section of undergraduate students and ii) we then measure their altruistic attitudes by means of a standard Dictator game. We observe that more socially integrated subjects are also more altruistic, as betweenness centrality and reciprocal degree are positively correlated with the level of giving, even after controlling for framing and social distance, which have been shown to significantly affect giving in previous studies. Our findings suggest that social distance and social integration are complementary determinants of altruistic behavior

This paper analyzes the effect on performance and earnings of delegating the wage choice to employees. Our results show that such delegation significantly increases effort levels. Moreover, we observe a Pareto-improvement, as the earnings of both employers and employees increase when employers delegate than when they do not. Interestingly, we also find that the employees' performance under delegation is higher than under non-delegation, even for similar wages. While there is strong evidence that behavior reflects strategic considerations, this result also holds for one-shot interactions. A possible non-strategic motivation explaining the positive reaction to delegation is a sense of enhanced responsibility.JEL Classification: C91, D01, J3, J41

This paper analyzes if men and women are expected to behave differently regarding altruism. Since the dictator game provides the most suitable design for studying altruism and generosity in the lab setting, we use a modified version to study the beliefs involved in the game. Our results are substantial: men and women are expected to behave differently. Moreover, while women believe that women are more generous, men consider that women are as generous as men.We appreciate comments from Josemari Aizpurua, Shoshana Neuman and participants in seminars at Bar-Ilan University, Max Planck Institute of Economics, Univ. Publica Navarra. Tim Cason and one anonymous referee made substantial comments on the previous draft. Financial support from CICYT (SEJ2007-62081/ECON and SEJ2006-00959/SOCI) and FCEA (SOC2.05/43) is gratefully acknowledge. Martha Gaustad revised the English grammar. Electronic supplementary materialThe online version of this article (http://dx

This paper explores the effect of the possibility of third-party intervention on behavior in a variant of the Berg, Dickhaut, and McCabe (1995) "Investment Game". A third-party's material payoff is not affected by the decisions made by the other participants, but this person may choose to punish a responder who has been overly selfish. The concern over this possibility may serve to discipline potentially-selfish responders. We also explore a treatment in which the third party may also choose to reward a sender who has received a low net payoff as a result of the responder's action. We find a strong and significant effect of third-party punishment, in both punishment regimes, as the amount sent by the first mover is more than 60% higher when there is the possibility of third-party punishment. We also find that responders return a higher proportion of the amount sent to them when there is the possibility of punishment, with this proportion slightly higher when reward is not feasible. Finally, third parties punish less when reward is feasible, but nevertheless spend more on the combination of reward and punishment when these are both permitted than on punishment when this is the only choice for redressing material outcomes.

Abstract:The notions of one's social identity and group membership have recently become topics for economic theory and experiments, and recent research has shown the importance of identity in a wide array of economic environments. But predictions are unclear when there is some trade-off between one's identity (e.g., race, gender, handedness) and potential monetary considerations. We conduct a public-goods experiment in which we permit endogenous groupformation. In a 2x2 design, we vary whether people participate in a team-building exercise and whether some people receive an endowment twice as much as others receive. We find that when both identity and financial considerations are present, high-endowment participants are strongly attracted to each other, with one's word-task-group affiliation eclipsed by the opportunity to earn more. Nevertheless, the team-building exercise greatly increases the level of contribution whether or not one is linked to people from one's team-building exercise.JEL Classification: A13, C91, C92, D03, J41