Bio

Abstract. An extensive experimental literature has documented miscoordination in establishing cooperative relationships when they can be supported in indefinitely repeated games: some people systematically try to cooperate, while others do not. The literature has had little success in finding personal characteristics that correlate systematically with these behaviors. We show that subjects who play the risky but efficient action in a simple coordination game (i.e., play stag in a stag hunt game) are significantly more likely to cooperate in indefinitely repeated games. This suggests that subjects who are less susceptible to strategic uncertainty are more likely to attempt to establish cooperative relationships.

Abstract. This study uses individual-level census data from Argentina to examine the socioeconomic disparities between Native and non-Native people. Native people fare worse across a variety of indicators, including housing, education, employment, and health. On average, the observed disparities amount to 12 percent of the standard deviation and persist even after controlling for factors such as geographic location. Furthermore, there are differences in the intergenerational transmission of education between Natives and non-Natives: for each level of education of the parents, the children of Natives have, on average, fewer years of education than the children of non-Natives. Finally, the study also reveals large differences between Native groups: while some achieve average outcomes that surpass those of the non-Native population, others significantly lag behind. Notably, these differences are correlated with a characteristic of their pre-Columbian economy: the practice of agriculture.

Abstract. We study the evolutionary robustness of strategies in infinitely repeated prisoners’ dilemma games in which players make mistakes with a small probability and are patient. The evolutionary process we consider is given by the replicator dynamics. We show that there is a large class of strategies with a uniformly large basin of attraction independent of the finite set of strategies involved. Moreover, we show that those strategies can not be unforgiving and, assuming that they are symmetric, they cooperate. We provide partial efficiency results for asymmetric strategies.

Abstract. Dal Bó et al. (2010) show experimentally that the effect of a policy may be greater when it is democratically selected than when it is exogenously imposed. In this paper we propose a new and simpler estimation strategy that does not require information on the vote of subjects in the exogenous treatment. The new estimation strategy is based on calculating the average behavior under democracy by weighting the behavior of each type of voter by its prevalence in the whole population (and not conditional on the vote outcome). We derive the distribution of this new weights-based estimator of the democracy effect and show it eliminates selection effects under certain conditions. We apply the new estimation strategy to the data in Dal Bó et al. (2010) and to the data from a new experiment for which we cannot use the previous estimation strategy as we do not have information on how subjects would have voted in the exogenous treatment. We find a significant democracy effect in the former but not on the latter application.

Abstract. We study the determinants of efficient behavior in stag hunt games (2×2 symmetric coordination games with Pareto ranked equilibria) using data from eight previous experiments on stag hunt games and a new experiment that allows for a more systematic variation of parameters. We find that subjects do not necessarily play the efficient action (stag), stressing the importance of strategic uncertainty in coordination games. While the frequency of playing stag is greater when stag is risk dominant, there is still large variation in behavior that cannot be explained by risk dominance. Part of this variation is explained by the risk arising from strategic uncertainty that we measure with the size of the basin of attraction of stag. We also explore the importance of other determinants of efficient behavior and we show that the results are robust to paying subjects using the lottery method in an attempt to induce risk neutral preferences.

Abstract. We use a novel experimental design to reliably elicit subjects' strategies in an infinitely repeated prisoner's dilemma experiment with perfect monitoring. We find that three simple strategies represent the majority of the chosen strategies: Always Defect, Tit-for-Tat, and Grim. In addition, we identify how the strategies systematically vary with the parameters of the game. Finally, we use the elicited strategies to test the ability to recover strategies using statistical methods based on observed round-by-round cooperation choices and find that this can be done fairly well, but only under certain conditions.

Abstract. Most of the political economy literature blames inefficient policies on institutions or politicians’ motives to supply bad policy, but voters may themselves be partially responsible by demanding bad policy. In this article, we posit that voters may systematically err when assessing potential changes in policy by underappreciating how new policies lead to new equilibrium behaviour. This biases voters towards policy changes that create direct benefits—welfare would rise if behaviour were held constant—even if those reforms ultimately reduce welfare because people adjust behaviour. Conversely, voters are biased against policies that impose direct costs even if they induce larger indirect benefits. Using a lab experiment, we find that a majority of subjects vote against policies that, while inflicting direct costs, would help them to overcome social dilemmas and thereby increase welfare. Subjects also support policies that, while producing direct benefits, create social dilemmas and ultimately hurt welfare. Both mistakes arise because subjects fail to fully anticipate the equilibrium effects of new policies. More precisely, we establish that subjects systematically underappreciate the extent to which policy changes will affect the behaviour of other people, and that these mistaken beliefs exert a causal effect on the demand for bad policy.

Abstract. A growing experimental literature studies the determinants of cooperation in infinitely repeated games, tests different predictions of the theory, and suggests an empirical solution to the problem of multiple equilibria. To provide a robust description of the literature's findings, we gather and analyze a metadata set of experiments on infinitely repeated prisoner's dilemma games. The experimental data show that cooperation is affected by infinite repetition and is more likely to arise when it can be supported in equilibrium. However, the fact that cooperation can be supported in equilibrium does not imply that most subjects will cooperate. High cooperation rates will emerge only when the parameters of the repeated game are such that cooperation is very robust to strategic uncertainty. We also review the results regarding the effect of imperfect monitoring, changing partners, and personal characteristics on cooperation and the strategies used to support it.

Abstract. The use of moral appeals to affect the behavior of others is pervasive (from the pulpit to ethics classes) but little is known about the effects of moral suasion on behavior. In a series of experiments we study whether moral suasion affects behavior in voluntary contribution games and the mechanisms by which behavior is altered. We find that observing a message with a moral standard according to the golden rule or, alternatively, utilitarian philosophy, results in a significant but transitory increase in contributions above the levels observed for subjects that did not receive a message or received a message that advised them to contribute without a moral rationale. When players have the option of punishing each other after the contribution stage, the effect of the moral messages on contributions becomes persistent: punishments and moral messages interact to sustain cooperation. We also investigate the mechanisms through which moral suasion operates and find that it affects both expectations and preferences.

Abstract. We incorporate appropriation activities (social conflict) into canonical models of trade and study how economic shocks and policies affect the intensity of conflict. We show that not all shocks that could make society richer reduce conflict: positive shocks to labor-intensive industries diminish conflict, while positive shocks to capital-intensive industries increase it. The key requirement is that conflict activities be more labor intensive than the economy as this determines how shocks affect the returns and costs of conflict. Our theory is consistent with several observed patterns of conflict and implies that empirical work should take into account the relative factor intensities of the productive and conflict sectors in each country. Incorporating appropriation into a canonic general equilibrium model affects what policies may be deemed desirable: in order to reduce conflict and generate Pareto-improvements policy must be distortionary, while reforms that appear efficiency-enhancing under the unrealistic assumption of perfect property rights may backfire. This offers one explanation for why reforms based on traditional models without appropriation may be delayed and become unpopular when implemented, and why societies may sympathize with seemingly inefficient redistribution.

Abstract. A usual criticism of the theory of infinitely repeated games is that it does not provide sharp predictions since there may be a multiplicity of equilibria. To address this issue, we present experimental evidence on the evolution of cooperation in infinitely repeated prisoner's dilemma games as subjects gain experience. We show that cooperation may prevail in infinitely repeated games, but the conditions under which this occurs are more stringent than the subgame perfect conditions usually considered or even a condition based on risk dominance. (JEL C71, C73)

Abstract. A novel experiment is used to show that the effect of a policy on the level of cooperation is greater when it is chosen democratically by the subjects than when it is exogenously imposed. In contrast to the previous literature, our experimental design allows us to control for selection effects (e.g., those who choose the policy may be affected differently by it). Our finding implies that democratic institutions may affect behavior directly in addition to having effects through the choice of policies. Our findings have implications for the generalizability of the results of randomized policy interventions. (JEL C91, D02, D12, D72)

Abstract. Many violent relationships are characterized by a high degree of cyclicality: women who are the victims of domestic violence often leave and return multiple times. To explain this we develop a model of time inconsistent preferences in the context of domestic violence. This time inconsistency generates a demand for commitment. We present supporting evidence that women in violent relationships display time inconsistent preferences by examining their demand for commitment devices. We find that no-drop policies – which compel the prosecutor to continue with prosecution even if the victim expresses a desire to drop the charges – result in an increase in reporting. No-drop policies also result in a decrease in the number of men murdered by intimates suggesting that some women in violent relationships move away from an extreme type of commitment device when a less costly one is offered.

Abstract. Political dynasties have long been present in democracies, raising concerns that inequality in the distribution of political power may reflect imperfections in democratic representation. However, the persistence of political elites may simply reflect differences in ability or political vocation across families and not their entrenchment in power. We show that dynastic prevalence in the Congress of the U.S. is high compared to that in other occupations and that political dynasties do not merely reflect permanent differences in family characteristics. On the contrary, using two instrumental variable techniques we find that political power is self-perpetuating: legislators who hold power for longer become more likely to have relatives entering Congress in the future. Thus, in politics, power begets power.

Abstract. We present a model where a long run player is allowed to use both money transfers and threats to influence the decisions of a sequence of short run players. We show that threats might be used credibly (even in arbitrarily short repeated games) by a long-lived player who gains by developing a reputation of carrying out punishments. Particular cases of the model are a long-lived pressure group offering rewards and punishments to a series of targets (public or corporate officials) in exchange for policy favors, or that of a long-lived extorter who demands money in order not to punish. We use the model to analyze the “convicted nonpayor” debate around judicial corruption. The model highlights formal similarities between lobbying and extortion.

Abstract. Previous literature has shown that demand fluctuations affect the scope for tacit collusion. I study whether discount factor fluctuations can have similar effects. I find that collusion depends not only on the level of the discount factor but also, and more surprisingly, on its volatility. Collusive prices and profits increase with a higher discount factor level, but decrease with its volatility. These results have important implications for empirical studies of collusive pricing, the role that collusive pricing may play in economic cycles and the study of cooperation in repeated games.

Abstract. This paper analyzes the outcomes that can be supported by social norms in a society of infinitely lived and patient agents that are randomly matched in pairs every period to play a given game. I find that any mutually beneficial outcome can be supported by a self-enforcing social norm under both perfect information and a simple local information system. These Folk Theorem results explain not only how social norms can provide incentives that support cooperation in a community, providing support to the concepts of social capital and corporate culture, but also how they can support inequality and discrimination.

Abstract. We present a model where groups attempt to influence policies using both bribes (plata, Spanish for silver) and the threat of punishment (plomo, Spanish for lead). We then use it to make predictions about the quality of a country's public officials and to understand the role of institutions granting politicians with immunity from legal prosecution. The use of punishment lowers the returns from public office and reduces the incentives of high-ability citizens to enter public life. Cheaper plomo and more resources subject to official discretion are associated with more frequent corruption and less able politicians. This predicts that violence in a country will typically go together with corruption and worse politicians. Moreover, the possibility of punishment changes the nature of the influence game, so that even cheaper plata can lower the ability of public officials. Protecting officials from accusations of corruption (immunity) will decrease the frequency of corruption if the judiciary is weak and may increase the quality of politicians. These predictions cannot emerge from a traditional model where only bribes are used.

Abstract. While there is an extensive literature on the theory of infinitely repeated games, empirical evidence on how "the shadow of the future" affects behavior is scarce and inconclusive. I simulate infinitely repeated prisoner's dilemma games in the lab with a random continuation rule. The experimental design represents an improvement over the existing literature by including sessions with finite repeated games as controls and a large number of players per session (which allows for learning without contagion effects). I find that the shadow of the future matters not only by significantly reducing opportunistic behavior, but also because its impact closely follows theoretical predictions.