Social interactions frequently take place under the shadow of the future. Previous literature explains cooperation in indefinitely repeated prisoner’s dilemma as driven predominantly by self-interested strategic considerations. This paper provides a causal test of the importance of social preferences in such contexts. In a series of pre-registered experiments, we show that high levels of cooperation can be sustained when prosocial individuals interact in segregated groups. By comparing their behavior with that of mixed and selfish groups, we highlight the conditions under which other-regarding motivations matter in repeated interactions.

Over the last four decades, a broad stream of experimental literature has been published using the Common Pool Resource (CPR) game to study how people react to congestible resources, and how to keep such resources from socially harmful overexploitation. With the goal of providing guidance to future work on this still-important paradigm, we provide a narrative review of the literature, summarizing the results for several key aspects of the experimental operationalization. We classify these aspects into two broad categories. The first describes ‘environmental’ assumptions on the modeled resource problem itself. This refers to aspects of the experimental environment reflecting factors such as group size, resource size and asymmetry of access, which generally constitute the nature of the dilemma. The second category involves ‘institutional’ issues related to how people might solve the problem, such as user communication between subjects, information about previous subjects’ choices, and regulatory measures.

Disappointment aversion has been suggested as an explanation for non-truthful rankings in strategy-proof school-choice matching mechanisms. We test this hypothesis using a novel experimental design that eliminates important alternative causes of non-truthful rankings. The design uses a simple contingent choice task with only two possible outcomes. Between two treatments, we manipulate the possibility for disappointment aversion to have an effect on ranking. We find a small and statistically marginally significant treatment effect in the direction predicted by disappointment aversion. We therefore conclude that disappointment aversion is a minor contributor to non-truthful rankings in strategy-proof school-choice matching mechanisms.

We introduce price freeze options into a model of sequential search. The model's predictions are tested in a laboratory experiment. The experiment varies (1) whether freezing is possible or not, (2) the cost of freezing, and (3) the time horizon. Overall, the observed treatment effects are consistent with the predictions of our model. Assuming that individuals experience regret, fail to ignore sunk search costs, misperceive the number of periods remaining, or are risk-averse, does not improve upon the performance of the model. Our results support the use of the assumption of optimal search behavior in theoretical and empirical studies.

Using public goods games in a laboratory setting, we study team-level production, where two teams compete for the resources of a common-member who can benefit from and provide effort in both teams. Intrinsically, the common-member faces divided loyalties. We examine such competition in a setting in which the common-member has productive abilities equal to that of the other team members (dedicated-members), and in two settings where he/she has greater relative potential. When effort (contributions) by the common-member have greater productivity (coupled with higher opportunity costs to contribute) in providing the public good relative to that of dedicated-members, we find team performance is not significantly increased. On the other hand, when the common-member has a greater endowment, sufficient to match the absolute contributions of team members in both teams, there is a significant increase in team performance. The evidence suggests that a norm of reciprocity by dedicated-members based on absolute contributions of the common-member better explains behavior than a norm based on the value added of the common-member's contributions. This behavior, along with fairness norms elicited in a survey, suggests that on average dedicated members do not sufficiently incorporate the common-members' higher opportunity costs in the treatment where his/her productivity is increased. This setting provides an important illustration of where the behavioral response to the type of inequality matters, leading to differences in team efficiency.

Past experimental research has shown that when rating systems are available, buyers are more generous in accepting unfair offers in ultimatum bargaining. However, it also suggests that, under these conditions, sellers behave more fairly to avoid receiving negative feedback. This paper experimentally investigates which effect is stronger with the use of a rating system: buyers’ inflated inequity acceptance or sellers’ disapproval aversion. We explore this question by varying the information condition on the buyers’ side. Our experiment shows that in a setup where the size of the pie is common knowledge for both buyers and sellers, when a rating system is present, the sellers exhibit disapproval aversion but the buyers do not display greater acceptance of inequity. By contrast, when only sellers are aware of the size of the pie, sellers behave aggressively to exploit buyers and their behavior does not change in the presence of a rating system; however, buyers display greater acceptance of inequity when a rating system is present. We discuss how these results can be explained by a theoretical model that includes sellers’ social disapproval aversion and buyers’ disappointment aversion in addition to the players’ inequality aversion.

This study reports experiments that examine outcomes when agents choose between a payment scheme that rewards based on absolute performance (i.e., piece rate) and a scheme that rewards based on relative performance (i.e., a tournament). Holding total payments in the tournament constant, performance is higher when the tournament option is winner-take-all compared to a graduated tournament (i.e., second and third-place performers also receive a payment). Performance is higher in the winner-take all tournaments even among participants that choose the piece-rate option. While there is a modest amount of overcrowding, there are no significant differences in overcrowding across conditions. Entry rates into the tournament and the relative ability of tournament entrants (compared to non-entrants in the same condition) are higher in the graduated tournament condition than the winner-take-all conditions. Consequently, the winner-take-all tournament is more efficient than the graduated tournament (incentive effects are stronger and the overcrowding is about the same), but the graduated tournament provides a more effective mechanism to identify the most capable performer in a talent pool.

This paper compares contributions to an experimental public good across the United States and Czech Republic, using a design that allows us to distinguish between altruism and decision error. Czech subjects contribute significantly more than American subjects, and further analysis reveals that this result cannot be attributed to the confounding effects of gender or decision error. Instead, preferences for altruism appear to differ across groups: Czechs are more altruistic than Americans and men are more altruistic than women.

Recently, there has been a Renaissance for multi-level selection models to explain the persistence of unselfish behavior in social dilemmas, in which assortative/correlated matching plays an important role. In the current study of a multi-round prisoners’ dilemma experiment, we introduce two correlated matching procedures that match subjects with similar action histories together. We discover significant treatment effects, compared to the control procedure of random matching. Particularly with the weighted history matching procedure we find bifurcations regarding group outcomes. Some groups converge to the all-defection equilibrium even more pronouncedly than the control groups do, while other groups generate much higher rate of cooperation, which is also associated with higher relative reward for a typical cooperative action. All in all, the data show that cooperation does have a much better chance to persist in a correlated/assortative-matching environment, as predicted in the literature.

The paper analyzes the effects of more intense competition on firms’ investments in process innovations. More intense competition corresponds to an increase in the number of firms or a switch from Cournot to Bertrand competition. We carry out experiments for two-stage games, where R&D investment choices are followed by product market competition. An increase in the number of firms from two to four reduces investments, whereas a switch from Cournot to Bertrand increases investments, even though theory predicts a negative effect in the four-player case. The results arise both in treatments in which both stages are implemented and in treatments in which only one stage is implemented. However, the positive effect of moving from Cournot to Bertrand competition is more pronounced in the former case.

Simulating a real world environment is of utmost importance for achieving accurate and meaningful results in experimental economics. Offering monetary incentives is a common method of creating this environment. In general, experimenters provide the rewards at the time of experiment. In this paper, we argue that receiving the reward at the time of the experiment may lead participants to make decisions as if the money they are using were not their own. To solve this problem, we devised a “prepaid mechanism” that encourages participants to use the money as if it were their own.

Several non-experimental studies claim that heterogeneity among individuals reduces trust. A few experimental studies have examined the effects of naturally-occurring differences among subjects on trusting behavior, and in contrast, most have not supported these claims. We adopt a novel approach by inducing heterogeneity among subjects in a canonical trust experiment. We accomplish this by varying the show-up payments given to subjects for participating in the experiment. We find that this induced inequality does not consistently affect first- or second-mover behavior in the classic trust game in the manner predicted by either previous theoretical work or empirical studies of survey-based measures of trust. Further, the effect of inequality on trust, in terms of both sign and significance, depends on whether show-up payments are awarded publicly or privately.

We use different incentive schemes to study truth-telling in a die-roll task when people are asked to reveal the number rolled privately. We find no significant evidence of cheating when there are no financial incentives associated with the reports, but do find evidence of such when the reports determine financial gains or losses (in different treatments). We find no evidence of loss aversion in the standard case in which subjects receive their earnings in a sealed envelope at the end of the session. When subjects manipulate the possible earnings, we find evidence of less cheating, particularly in the loss setting; in fact, there is no significant difference in behavior between the non-incentivized case and the loss setting with money manipulation. We interpret our findings in terms of the moral cost of cheating and differences in the perceived trust and beliefs in the gain and the loss frames.

Using a laboratory experiment, we investigate whether a variety of behaviors in repeated games are related to an array of individual characteristics that are popular in economics: risk attitude, time preference, trust, trustworthiness, altruism, strategic skills in one-shot matrix games, compliance with first-order stochastic dominance, ability to plan ahead, and gender. We do find some systematic relationships. A subject’s compliance with first-order stochastic dominance as well as, possibly, patience, gender, and altruism have some systematic effects on her behavior in repeated games. At the level of a pair of subjects who are playing a repeated game, each subject’s gender as well as, possibly, patience and ability to choose an available dominant strategy in a one-shot matrix game systematically affect the frequency of the cooperate–cooperate outcome. However, overall, the number of systematic relationships is surprisingly small.

We report evidence from an experiment where an employer selects one of two workers to perform a task for a fixed compensation. Workers differ in their ability. The employer’s payoff depends on the worker’s ability and on a non-contractible effort that the worker exerts once employed. We find that selected workers exert an effort higher than the minimum enforceable one. When the employers can send a free-text form message to the selected worker, workers with low ability exert significantly higher effort than the workers with high ability. The difference in effort overcompensates the difference in ability.

We investigate the endogenous formation of sanctioning institutions supposed to improve efficiency in the voluntary provision of public goods. Our paper parallels Markussen et al. (Rev Econ Stud 81:301–324, 2014) in that our experimental subjects vote over formal versus informal sanctions, but it goes beyond that paper by endogenizing the formal sanction scheme. We find that self-determined formal sanctions schemes are popular and efficient when they carry no up-front cost, but as in Markussen et al. informal sanctions are more popular and efficient than formal sanctions when adopting the latter entails such a cost. Practice improves the performance of sanction schemes: they become more targeted and deterrent with learning. Voters’ characteristics, including their tendency to engage in perverse informal sanctioning, help to predict individual voting.