To examine the effect of group size on the stability of prosocial behavior we used standard one-shot public good experiments with two and four subjects, which were conducted repeatedly three times at intervals of one week. Partner and stranger treatments were employed to control for group...

The dynamics of behavior observed in standard public-good experiments can be explained by imperfect conditional cooperation combined with social learning (Fischbacher and Gächter, 2010). But it is unclear what determines first-round contributions. We argue that first-round contributions depend...

According to the model of HOEL (1991), a unilateral emissions abatement of a global pollutant leads to lower aggregated emissions in a game with a simultaneous decision protocol. Our experiment tests the Hoel model and examines the question of whether a leader can induce additional abatement of...