We study the effects of competition in a context in which people's actions can not be contractually fixed. We find that in such an environment the very presence of competition does neither increase efficiency nor does it yield any payoff gains for the short side of the market. We also find that...

The formation of social ties is examined in an experimental study of voluntary public good provision. The experiment consists of three parts. In the first part the value orientation (attitude to a generalized other) ismeasured. In the second part couples play 25 periods of a public good game. In...

Empirical research suggests that - rather than improving incentives - exerting controlcan reduce workers' performance by eroding motivation. The present paper shows thatintention-based reciprocity can cause such motivational crowding-out if individuals differin their propensity for reciprocity...

We experimentally study the relationship between other-regarding preferences, group identity and political participation. In doing so, we propose a novel group identity induction procedure that succeeds in creating environments where in-group bias is either high or low. At the individual level,...

Economic behavior often takes place in groups of small numbers of peopleinteracting with each other (like work teams, neighborhoods, socialnetworks, etc.). Characteristic of such interaction is the development of(affective) interpersonal relationships, or social ties. According tosociologists,...

Power index research has been a very active field in the last decades. Will this continue or are all the important questions solved? We argue that there are still many opportunities to conduct useful research with and on power indices. Positive and normative questions keep calling for...

Health shocks are among the most important unprotected risks for microfinance clients, but the take-up of micro health insurance typically remains limited. This paper attributes low enrolment rates to a social dilemma. Our theory is that in jointly liable groups, insurance is a public good....

Transparent decision-making processes are widely regarded as a prerequisite for the working of a representative democracy. It facilitates accountability, and citizens may suspect that decisions, if taken behind closed doors, do not promote their interests. Why else the secrecy? We provide a...

A ranking method assigns to every weighted directed graph a (weak) orderingof the nodes. In this paper we axiomatize the ranking method that ranksthe nodes according to their outflow using four independent axioms. This outflowranking method generalizes the ranking by outdegree for directed...

In experimental investigations of the effect of real incentives, accountability—the implicit or explicit expectation of a decision maker that she may have to justify her decisions in front of somebody else—is often confounded with the incentives themselves. This confounding of accountability...