Are initial competitive advantages self-reinforcing, so that markets exhibit an endogenous tendency to be dominated by only a few firms? Although this question is of great economic importance, no systematic empirical study has yet addressed it. Therefore, we examine experimentally whether firms...

The paper shows that, in some important respects, the differences between the Nash equilibrium and competing concepts such as the quantalresponse equilibrium are smaller than they appear. I start from the observation that, in many experiments, parameter shifts that leave the Nash equilibrium...

We investigate how group boundaries, and the economic environment surrounding groups, affect altruistic cooperation and punishment behavior. Our study uses experiments conducted with 525 officers in the Swiss Army, and exploits random assignment to platoons. We find that, without competition...

In this paper, we propose a decision framework where people are individually asked to either actively consent to or dissent from some pro-social behavior. We hypothesize that confronting individuals with the choice of whether to engage in a specific pro-social behavior contributes to the...

There is a longstanding concern that material incentives might undermine prosocial motivation, leading to a decrease in blood donations rather than an increase. This paper provides an empirical test of how material incentives affect blood donations in a large-scale field experiment spanning...

In this paper, we propose a decision framework where people are individually asked to either actively consent or dissent to some pro-social behavior. We hypothesize that confronting individuals with the choice of engaging in a specific pro-social behavior contributes to the formation of...

Due to incomplete contracts, efficiency of an organization depends on willingness of individuals to take non-selfish actions, such as cooperating when there is no incentive to do so or punishing inefficient actions by others. Organizations also constitute a social boundary, or group. We...