There is continuing debate about what explains cooperation and self-sacrifice in nature and in particular in humans. This paper suggests a new way to think about this famous problem. I argue that, for an evolutionary biologist as well as a quantitative social scientist, the triangle of two...

In this paper we investigate how cognitive ability and character skills influence behavior, success and the evolution of play towards Nash equilibrium in repeated strategic interactions. We study behavior in a p-beauty contest experiment and find striking differences according to cognitive...

Intelligence affects social outcomes of groups. A systematic study of the link is provided in an experiment where two groups of subjects with different levels of intelligence, but otherwise similar, play a repeated prisoner's dilemma. The initial cooperation rates are similar, it increases in...

We study the dynamics of the private provision of a public good that requires both capacity buildup and ongoing operating costs. We show that setting a time limit for the collection of contributions dedicated to capacity buildup minimizes the utility loss at the Nash equilibrium. We test the...

This paper presents a Schelling-type checkerboard model of residential segregation formulated as a spatial game. It shows that although every agent prefers to live in a mixed-race neighborhood, complete segregation is observed almost all of the time. A concept of tipping is rigorously defined,...

We examine rational learning among expert chess players and how they update their beliefs in repeated games with the same opponent. We present a model that explains how equilibrium play is affected when players change their choice of strategy when receiving additional information from each...

In this article, a modelling framework for the information transmission between agents in an evolutionary game setting is proposed. Agents observe traits which reflect past and present behaviour and success of other agents. If agents imitate more successful agents based on these traits, the...

In this paper we analyze the frequently observed phenomenon that (i) some members of a team ("black sheep") exhibit behavior disliked by other (honest) team members, who (ii) nevertheless refrain from reporting such misbehavior to the authorities (they set up a "wall of silence"). Much cited...

Charles Darwin (1874) stated that "women are less selfish but men are more competitive". Very recent papers (Eckel & Grossman, 1998, 2001 or Andreoni and Vesterlund 2001, among others) have shown the relevance of gender in altruism in both ultimatum and dictator games. In this paper we analyze...

We develop a model of strategic contractual incompleteness that identifies conditions under which principals might omit even costlessly verifiable terms. We then use experiments to test comparative statics predictions of the model. While it is well known that verifiability imperfections can...