We compare the behaviour of students and professional traders from an influential German bank in an experiment involving financial options. The arbitrage free option price is independent of the probability distribution of the underlying asset. The experimental data uncover a probability...

The game-theoretic assumption of ‘common knowledge of rationality’ leads to paradoxes when rationality is represented in a Bayesian framework as cautious expected utility maximization with independent beliefs (ICEU). We diagnose and resolve these paradoxes by presenting a new class of formal...

Experimental dictator games have been used to explore unselfish behaviour. Evidence is presented here, however, that subjects’ generosity can be reversed by allowing them to take money from a partner. Dictator game giving therefore does not stem from orthodox social preferences. It can be...

We compare social preference and social norm based explanations for peer effects in a three-person gift-exchange game experiment. In the experiment a principal pays a wage to each of two agents, who then make effort choices sequentially. In our baseline treatment we observe that the second...

Recent theoretical research on oligopolistic competition suggests that prices may increase when more firms compete in a market. However, this finding is based on comparative-static analyses of static models, which overlook the possibility that sellers may be able to charge supra-competitive...

We study the interplay between leading-by-example and group identity in a public goods game experiment. A common identity between the leader and her followers is beneficial for cooperation: average contributions are more than 30% higher than in a treatment where no identity was induced. In two...

We experimentally investigate cooperation in privileged groups which according to Olson (1965) are groups in which at least one member has an incentive to supply a positive amount of the public good. More specifically, we analyze group member heterogeneity with respect to two dimensions:...

Many important decisions are taken according to weighted majority rule. Power indices predict that enlargement of the voting body may affect the balance of power between the original members even if their number of votes and the decision rule remain constant. Some of the existing voters may...

Using belief elicitation, the paper investigates the formation and the evolution of beliefs in a signalling game in which a common prior on Sender's type is not induced. Beliefs are elicited about the type of the Sender and about the strategies of the players. The experimental subjects often...

Philosophers and economists write about collective action from distinct but related points of view. This paper aims to bridge these perspectives. Economists have been concerned with rationality in a strategic context. There, problems posed by “coordination games” seem to point to a form of...