We investigate whether automatic selling devices causally reduce investors' disposition effect (DE) in a laboratory experiment. Investors can actively buy and sell assets. Investors in the treatment group use stop-loss and take-gain options to automatically sell assets. In addition, we introduce a reminder condition that reminds investors about their selling plan if a limit is hit. Results show that the automatic selling device treatment significantly reduces the DEs, but the reminder treatment does not. Thus, the opportunity to ex ante commit to automatically selling at a loss causally reduces the disposition effect.

One lingering puzzle is why voluntary contributions to public goods decline over time in experimental and real-world settings. We show that the decline of cooperation is driven by individual preferences for imperfect conditional cooperation. Many people's desire to contribute less than others, rather than changing beliefs of what others will contribute over time or people's heterogeneity in preferences makes voluntary cooperation fragile. Universal free riding thus eventually emerges, despite the fact that most people are not selfish. (D12, D 83, H41, Z13)

We report experimental results for a simple bimatrix game between a manager and an auditor. We investigate whether the quality of audited financial statements improves if the relative proportion of perfectly honest auditors increases. We find that the quality of audited reports is higher if computerized auditors who always perform a high audit effort are present. This result is in direct contrast to the Nash prediction for our game. The Quantal Response Equilibrium, which explicitly takes into account boundedly rational behavior, supports our experimental data. Our main findings depend neither on framing nor the payoff matrix we use.

The disposition effect, i.e., the tendency to sell winning stocks too early and losing stocks too late is one of the most frequently observed and discussed biases of financial investors. We investigate in a laboratory experiment whether the option of automatic selling devices causally reduces investors’ disposition effect. Our investors can actively buy and sell assets, and, in the treatment group, additionally use stop-loss and take-gain options to automatically sell assets. Investors who had access to the automatic selling devices had significantly smaller disposition effects. The reduction was driven by a significant increase in realized losses. The proportion of winners realized was similar in both treatments. Additionally, our setup provides new evidence on which reference prices investors relate to when choosing limits for automatic sales.

This paper investigates the driving forces behind informal sanctions in cooperation games and the extent to which theories of fairness and reciprocity capture these forces. We find that cooperators' punishment is almost exclusively targeted toward the defectors, but the latter also impose a considerable amount of spiteful punishment on the cooperators. However, spiteful punishment vanishes if the punishers can no longer affect the payoff differences between themselves and the punished individual, whereas the cooperators even increase the resources devoted to punishment in this case. Our data also discriminate between different fairness principles. Fairness theories that are based on the assumption that players compare their own payoff to the group's average or the group's total payoff cannot explain the fact that cooperators target their punishment at the defectors. Fairness theories that assume that players aim to minimize payoff inequalities cannot explain the fact that cooperators punish defectors even if payoff inequalities cannot be reduced. Therefore, retaliation, i.e., the desire to harm those who committed unfair acts, seems to be the most important motive behind fairness-driven informal sanctions. Copyright The Econometric Society 2005.

Neuroeconomic Foundations of Trust and Social Preferences: Initial Evidence by Ernst Fehr, Urs Fischbacher and Michael Kosfeld. Published in volume 95, issue 2, pages 346-351 of American Economic Review, May 2005