Both in the field and in the lab, participants frequently cooperate, despite the fact that the situation can be modelled as a simultaneous, symmetric prisoner's dilemma. This experiment manipulates the payoff in case both players defect, and explains the degree of cooperation by a combination of...

Punishees regularly ask for justification. But is justification also effective? To answer this question under controlled conditions, we have conducted a public goods experiment with central punishment. The authority is neutral - she does not benefit from contributions to the public good....

We use survey and experimental data to explore how effort choices and preferences for redis-tribution are linked. Under standard preferences, redistribution would reduce effort. This is different with social preferences. Using data from the World Value Survey, we find that respondents with...

The standard tool for analysing social dilemmas is game theory. They are reconstructed as prisoner dilemma games. This is helpful for understanding the incentive structure. Yet this analysis is based on the classic homo oeconomicus assumptions. In many real world dilemma situations, these...

Anti-trust cases more often than not hinge upon market definition. The anti-trust authorities use standardised tests for the purpose, like the small but significant and nontransitory increase in price test prevalent in US law. These tests are often read as neoclassical economics, watered down to...

Experimental participants are more likely to follow an arbitrary rule the more of their peers do so as well. The difference between unconditional and conditional rule following is most pronounced for individuals who follow few rules unconditionally.

Policymakers all over the world claim: no innovation without protection. For more than a century, critics have objected that the case for intellectual property is far from clear. This paper uses a game theoretic model to organise the debate. It is possible to model innovation as a prisoner's...

The market for copyrights is characterised by a highly skewed distribution of profits: very few movies, books and songs generate huge profits, whereas the great bulk barely manages to recover production cost. At the moment when the owner of intellectual property grants a licence ('ex ante'),...