One-way communication has been found to substantially increasecontributions in linear voluntary contribution mechanisms. We confirmthe robustness of this result in the presence of income heterogeneity.

Previous research indicates that risky and uncertain marginal returnsfrom the public good significantly lower contributions. This paper presentsexperimental results illustrating that the effects of risk and uncertainty dependon the employed parameterization. Specifically, if the value of the...

This paper provides a new way to identify conditional cooperationin a real-time version of the standard voluntary contribution mechanism. Ourapproach avoids most drawbacks of the traditional procedures because it relieson endogenous cycle lengths, which are defined by the number of contributors...

We use a two-person public goods experiment to distinguish betweene±ciency and fairness as possible motivations for cooperative behavior.Asymmetric marginal per capita returns allow only the high-productivityplayer to increase group payo®s when contributing positive amounts....

We adopt an evolutionary approach to investigate whether and when condi-tional cooperation can explain the voluntary contribution phenomenon oftenobserved in public goods experiments and in real life. Formally, conditionalcooperation is captured by a regret parameter describing how much an...

Similar to Levati and Neugebauer (2001), a clock is used by which participantscan vary their individual contributions for voluntarily providing apublic good. As time goes by, participants either in(de)crease their contributiongradually or keep it constant. Groups of two poorly and two...

We conducted a laboratory study with a public goods game in which contributions are notsubmitted all at once but incrementally as coordinated in real time by a clock. Individualspress a button as soon as the clock equals their willingness to contribute. This publicgoods institution exploits the...

We use a two-person public goods experiment to distinguish between effciency and fairness as possible motivations for cooperative behavior. Asymmetric marginal per capita returns allow only the high-productivity player to increase group payoffs when contributing positive amounts. Asymmetric...

In a public goods experiment, subjects can vary over a period of stochastic length two contribution levels: one is publicly observable (their cheap talk stated intention), while the other is not seen by the others (their secret intention). When the period suddenly stops, participants are...

We report on an experiment designed to explore whether allowing individuals to voice their anger prevents costly punishment. For this sake, we use an ultimatum minigame and distinguish two treatments: one in which responders can only accept or reject the o®er, and the other in which they can...