There is strong evidence that people exploit their bargaining power in competitive markets but not in bilateral bargaining situations. There is also strong evidence that people exploit free-riding opportunities in voluntary cooperation games. Yet, when they are given the opportunity to punish...

One of the most basic questions in economics concerns the effects of competition on market prices. We show that the neglect of both fairness concerns and decision errors prevents a satisfactory understanding of how competition affects prices. We conducted experiments which demonstrate that the...

A substantial number of people exhibit social preferences, which means they are not solely motivated by material self-interest but also care positively or negatively for the material payoffs of relevant reference agents. We show empirically that economists fail to understand fundamental economic...

Most economic models are based on the self-interest hypothesis that assumes that all people are exclusively motivated by their material self-interest. In recent years experimental economists have gathered overwhelming evidence that systematically refutes the self-interest hypothesis and suggests...

Is competition perceived as a fair procedure? We report data from laboratory experiments where a powerful buyer can trade with one of several sellers. Sellers who feel shortchanged can engage in counterproductive behavior to punish the buyer. We find that the same unfavorable terms of trade...

Teamwork and cooperation between workers can be of substantial value to a firm, yet the level of worker cooperation often varies between individual firms. We show that these differences can be the result of labor market competition if workers have heterogeneous preferences and preferences are...

Chapter written for the Handbook of Reciprocity, Gift-Giving and Altruism

Most economic models are based on the self-interest hypothesis that assumes that all people are exclusively motivated by their material self-interest. In recent years experimental economists have gathered overwhelming evidence that systematically refutes the self-interest hypothesis and suggests...

This paper surveys recent experimental and field evidence on the impact of concerns for fairness, reciprocity and altruism on economic decision making. It also reviews some new theoretical attempts to model the observed behavior.