Ernesto Reuben

This is an experimental study of negative reciprocity in the case of multiple reciprocators. We use a three-player power-to-take game where a proposer is matched with two responders. We compare a treatment in which responders are anonymous to each other (strangers) with one in which responders know each other from outside the lab (friends). We focus on the responders’ decisions, beliefs, and emotions. Our main findings are: (1) friends punish the proposer more than strangers, (2) friends are more likely to coordinate their punishment (without communication), and (3) both punishment and coordination are explained by the responders' emotional reactions.

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In public good provision, privileged groups enjoy the advantage that some of its members find it optimal to supply a positive amount of the public good. However, their inherent asymmetric nature may make the enforcement of cooperative behavior through informal sanctioning harder to accomplish. In this paper we experimentally investigate public good provision in normal and privileged groups with and without decentralized punishment. We find that compared to normal groups, privileged groups are relatively ineffective in using costly sanctions to increase everyone's contributions. Punishment is less targeted towards strong free-riders and they exhibit a weaker increase in contributions after being punished. Thus, we show that privileged groups are not as privileged as they initially seem.

This paper experimentally explores how the enforcement of cooperative behavior in a social dilemma is facilitated through institutional as well as emotional mechanisms. Recent studies emphasize the importance of anger and its role in motivating individuals to punish free riders. However, we find that anger also triggers retaliatory behavior by the punished individuals. This makes the enforcement of a cooperative norm more costly. We show that in addition to anger, ‘social’ emotions like guilt need to be present for punishment to be an effective deterrent of uncooperative actions. They play a key role by subduing the desire of punished individuals to retaliate and by motivating them to behave more cooperatively in the future.

In this paper, we study the effectiveness of intergroup competition in promoting cooperative behavior. We focus on intergroup competition that is non-rival in the sense that everyone can be a winner. This type of competition does not give groups an incentive to outcompete others. However, in spite of this fact, we find that intergroup competition produces a universal increase in cooperation. Furthermore, in settings where there are strong incentives to compete, intergroup competition benefits a majority of individuals.

This paper shows that there is a positive and statistically significant correlation between the short-term discount rate over a monetary reward and the short-term discount rate over a primary reward (chocolate). In particular, for subjects who like chocolate and are hungry. This suggests that monetary rewards are suitable for the study of inter-temporal choice. In fact, given the problems associated with the use of primary rewards (differing tastes for the good, hunger, and possible satiation), we argue that measurement with monetary rewards is more reliable.

We study experimentally the effect of expectations on trustworthiness. Most subjects respond with untrustworthy behavior if they find out that little is expected from them. This suggests that guilt aversion plays an important role in inducing trustworthiness.

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We use a novel experimental design to distinguish strategic from non-strategic motives for cooperation in social dilemmas. By using the strategy method in a repeated sequential prisoners' dilemma with a known probabilistic end, we can differentiate between end-game and non-end-game behavior. Individuals that cooperate non-strategically do not change their behavior depending on whether the game continues or not. In contrast, strategically-motivated individuals cooperate only if the game continues and otherwise defect. Our design allows us to control for learning effects and beliefs concerning the cooperativeness of others. Results with two different subject pools indicate that the most common motive for cooperation is indeed strategic. Moreover, strategic motivations also explain most of the commonly-observed pattern of conditional cooperation.

There is a large body of literature documenting both a preference for immediacy and a tendency to procrastinate. O'Donoghue and Rabin (1999a,b, 2001) and Carroll et al. (2007) model these behaviors as two facets of the same phenomenon. In this paper, we use a combination of lab and field evidence to study whether these two types of behavior are indeed linked. To measure immediacy we had subjects choose between a series of smaller-sooner and larger-later rewards. Both rewards were paid by check to control for transaction costs. To measure procrastination we record how fast subjects cash their checks and complete other tasks. Our results lend support to the hypothesis that subjects who have a preference for immediacy are more likely to procrastinate. We also find evidence that subjects differ in the degree with which they anticipate their own procrastination, that is, in their degree of "sophistication" in the O'Donoghue and Rabin (1999a) terminology.

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Most models of conflict concentrate on how players allocate resources between productive and fighting efforts. After a conflict, the winner is assumed to take control of all the resources of the loser. In this paper we show experimentally that this simplification misses an important component of a conflict, namely the reaction of the defeated player. We find that, if given the choice to destroy some of their resources, many defeated players prefer to do so rather than let the winner take any of it. Given this, incentives to invest in weapons as opposed to production change and in some cases lower levels of conflict are achieved. Furthermore in settings with repeated interaction, the behavior of players in post-conflict stages can serve as a form of costly communication which enables players to reach a peaceful outcome in the future.

This experimental study investigates how behavior changes after punishment for a selfish action. The focus is on how proposers in a power-to-take game adjust their behavior depending on their fairness perceptions, their experienced emotions, and their interaction with responders. We find that fairness plays an important role. Fair-minded proposers tend to feel less regret when they learn they could have taken more. Furthermore, proposers who take more than their perceived fairness norm feel more shame. This induces proposers to lower their claims. We also find that the perceived fairness norm varies considerably between individuals. Therefore, it is not the case that proposers who considered themselves fair are particularly nice to responders.

This document describes the data analyzed in the Templeton-Chicago MBAs longitudinal study. The study is based on the entire 2008 generation of MBA students from Chicago University’s Graduate School of Business. The data described in this document are obtained from three different sources: surveys, laboratory experiments, and the GSB’s admission department. We give a brief overview of each data source, in addition to a detailed description of the data-collection procedures.

Fairness norms are an elusive and yet important characteristic of our societies. In many situations of interest to economists, the active enforcement of fairness norms affect behavior in significant ways. This thesis studies the motivations of individuals to comply with and to enforce fairness norms. Furthermore, the circumstances under which the enforcement of fairness norms leads to desirable outcomes are investigated. Particular attention is given to the effects of punishment, fairness perceptions, and emotions on an individual’s willingness to behave in a fair manner. Latter chapters study norm enforcement in public good settings. First, in groups with heterogeneous endowments, and second, in groups that have less free riding incentives but suffer from the fact that high cooperation levels are no longer supported by fairness norms.

Explaining collective action is still one of the most challenging problems for the social sciences. The purpose of this paper is to describe how the main ideas on the subject have evolved over the years and additionally, to illustrate how our understanding of the problem has grown. It starts by describing perhaps the most influential model in the literature, namely Olson’s model of collective action. Later on, it uses the same model to relate six essentially different approaches to solve the collective action problem; for each, highlighting their contributions to our general understanding as well as their main drawbacks. I conclude by stressing the fact that we still do not have a satisfactory theory of collective action. However, recent work is described which uses cognitively and emotionally bounded agents and promises to deliver significant improvements.