The Internet globalizes the world. National regulatory autonomy shrinks. Transferring data from one country to another is almost costless. Foreign content is just a click away. Why is it that states have been able to re-install co-existence in some policy areas, and not in others? In data...

Broken Windows: the metaphor has changed New York and Los Angeles. Yet it is far from undisputed whether the broken windows policy was causal for reducing crime. In a series of lab experiments we show that first impressions are indeed causal for cooperativeness in three different institutional...

Does probation pay a double dividend? Society saves the cost of incarceration, and convicts preserve their liberty. But does probation also reduce the risk of recidivism? In a meta-study we show that the field evidence is inconclusive. Moreover it struggles with an identification problem: those...

The most famous element in Bentham's theory of punishment, the Panopticon Prison, expresses his view of the two purposes of punishment, deterrence and special prevention. We investigate Bentham's intuition in a public goods lab experiment by manipulating how much information on punishment...

Cartels are inherently instable. Each cartelist is best off if it breaks the cartel, while the remaining firms remain loyal. If firms interact only once, if products are homogenous, if firms compete in price, and if marginal cost is constant, theory even predicts that strategic interaction...

Providing public goods is hard, because providers are best off free-riding. Is it even harder if one group's public good is a public bad for another group or, conversely, gives the latter a windfall profit? We experimentally study public goods provision embedded in a social context and find that...

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...

Cooperation problems are at the heart of many everyday situations. In this paper, we propose a very simple and light-handed mechanism to sustain cooperation and test its performance in a rich laboratory environment. The mechanism moderates cooperation by controlling experiences, more...

Evidence from an experiment investigating the "house money effect" in the context of a public goods game is reconsidered. Analysis is performed within the framework of the panel hurdle model, in which subjects are assumed to be one of two types: free-riders, and potential contributors. The...