In their majority, public international lawyers postulate that for a new rule of customary law to originate, two conditions must be fulfilled: there must be consistent practice, and it must be shown that this practice is motivated by the belief that such behaviour is required in law. Maurice...

We report evidence from public goods experiments with and without punishment which we onducted in Russia with 566 urban and rural participants of young and mature age cohorts. Russia is interesting for studying voluntary cooperation because of its long history of collectivism, and a huge...

If two players of a simultaneous symmetric one-shot prisoner's dilemma hold standard prefer-ences, the fact that choosing the cooperative move imposes harm on a passive outsider is imma-terial. Yet if participants hold social preferences, one might think that they are reticent to impose harm on...

Customary law has been criticized from very different angles. Rational choice theorists claim that what looks like custom is nothing but self-interest. Positivists doubt that anything beyond consent assumes the force of law. In this paper, we adopt an experimental approach to test these claims....

Arguably, for many citizens the perceived expected disutility from sanctions is smaller than the monetary gain from tax evasion. Nevertheless most people pay their taxes most of the time. In a lab experiment, we show that the willingness to pay taxes even absent enforcement is indeed pronounced....

Arguably, for many citizens the perceived expected disutility from sanctions is smaller than the monetary gain from tax evasion. Nevertheless most people pay their taxes most of the time. In a lab experiment, we show that the willingness to pay taxes even absent enforcement is indeed pronounced....

We investigate whether there is a link between conditional cooperation and betrayal aversion. We use a public goods game to classify subjects by type of contribution preference and by belief about the contributions of others; and we measure betrayal aversion for different categories of subject....

We investigate whether there is a link between conditional cooperation and betrayal aversion. We use a public goods game to classify subjects by type of contribution preference and by belief about the contributions of others; and we measure betrayal aversion for different categories of subject....

We investigate whether there is a link between conditional cooperation and betrayal aversion. We use a public goods game to classify subjects by type of contribution preference and by belief about the contributions of others; and we measure betrayal aversion for different categories of subject....

In their majority, public international lawyers postulate that for a new rule of customary law to originate, two conditions must be fulfilled: there must be consistent practice, and it must be shown that this practice is motivated by the belief that such behaviour is required in law. Maurice...