CONVERGENCE: AN EXPERIMENTAL STUDY OF TEACHING AND LEARNING IN REPEATED GAMES

Nash equilibrium can be interpreted as a steady state where players hold correct beliefs about the other players’ behavior and act rationally. We experimentally examine the process that leads to this steady state. Our results indicate that some players emerge as teachers—those subjects who, by their actions, try to influence the beliefs of their opponent and lead the way to a more favorable outcome—and that the presence of teachers appears to facilitate convergence to Nash equilibrium. In addition to our experiments, we examine games, with different properties, from other experiments and show that teaching plays an important role in these games. We also report results from treatments in which teaching is made more difficult. In these treatments, convergence rates go down and any convergence that does occur is delayed.     

FORGETTING WE FORGET: OVERCONFIDENCE AND MEMORY

Do individuals have unbiased beliefs, or are they over‐ or underconfident? Overconfident individuals may fail to prepare optimally for the future, and economists who infer preferences from behavior under the assumption of unbiased beliefs will make mistaken inferences. This paper documents overconfidence in a new domain, prospective memory, using an experimental design that is more robust to potential confounds than previous research. Subjects chose between smaller automatic payments and larger payments they had to remember to claim at a six‐month delay. In a large sample of college and MBA students at two different universities, subjects make choices that imply a forecast of a 76% claim rate, but only 53% of subjects actually claimed the payment.     

IMAGE AND MISREPORTING

In this paper we analyze how image utility can lead to misreporting of private information in contexts where truthful reports maximize monetary outcomes. In a controlled experiment, subjects go through a series of quiz questions and subsequently report a performance measure. We vary whether reports are made to an audience or not. In an additional feedback treatment, reports are also stated to an audience and afterwards the experimenter publicly verifies whether reports were correct. We find that in the audience treatment, stated reports are significantly higher relative to the private treatment as well as the feedback treatment. Our findings suggest that overconfident appearance might be a consequence of social approval seeking.     

DEBT,POLICY UNCERTAINTY,AND EXPECTATIONS STABILIZATION

This paper develops a model of policy regime uncertainty and its consequences for stabilizing expectations. Because of learning dynamics, uncertainty about monetary and fiscal policy is shown to restrict, relative to a rational expectations analysis, the set of policies consistent with macroeconomic stability. Anchoring expectations by communicating about monetary and fiscal policy enlarges the set of policies consistent with stability. However, absent anchored fiscal expectations, the advantages from anchoring monetary expectations are smaller the larger is the average level of indebtedness. Finally, even when expectations are stabilized in the long run, the higher are average debt levels the more persistent will be the effects of disturbances out of rational expectations equilibrium.     

WILLPOWER AND THE OPTIMAL CONTROL OF VISCERAL URGES

Common intuition and experimental psychology suggest that the ability to self‐regulate (willpower) is a depletable resource. We investigate the behavior of an agent with limited willpower who optimally consumes over time an endowment of a tempting and storable consumption good or cake. We assume that restraining consumption below the most tempting feasible rate requires willpower. Any willpower not used to regulate consumption may be valuable in controlling other urges. Willpower thus links otherwise unrelated behaviors requiring self‐control. An agent with limited willpower will display apparent domain‐specific time preference. Such an agent will almost never perfectly smooth his consumption, even when it is feasible to do so. Whether the agent relaxes control of his consumption over time as experimental psychologists predict or tightens it as most behavioral theories predict depends in our model on the net effect of two analytically distinct but opposing forces.     

PREDICTING LOTTO NUMBERS: A NATURAL EXPERIMENT ON THE GAMBLER'S FALLACY AND THE HOT‐HAND FALLACY

We investigate the “law of small numbers” using a data set on lotto gambling that allows us to measure players' reactions to draws. While most players pick the same set of numbers week after week, we find that those who do change, react on average as predicted by the law of small numbers as formalized in recent behavioral theory. In particular, players tend to bet less on numbers that have been drawn in the preceding week, as suggested by the “gambler's fallacy”, and bet more on a number if it was frequently drawn in the recent past, consistent with the “hot‐hand fallacy”.     

MEASURING INTERTEMPORAL SUBSTITUTION: THE IMPORTANCE OF METHOD CHOICES AND SELECTIVE REPORTING

I examine 2,735 estimates of the elasticity of intertemporal substitution in consumption (EIS) reported in 169 published studies. The literature shows strong selective reporting: researchers discard negative and insignificant estimates too often, which pulls the mean estimate up by about 0.5. The reporting bias dwarfs the effects of methods, with the exception of the choice between micro and macro data. When I correct the mean for the bias, for macro estimates I get zero, even though the reported t‐statistics are on average two. The corrected mean of micro estimates of the EIS for asset holders is around 0.3–0.4. Calibrations greater than 0.8 are inconsistent with the bulk of the empirical evidence.     

A MODEL OF NONBELIEF IN THE LAW OF LARGE NUMBERS

People believe that, even in very large samples, proportions of binary signals might depart significantly from the population mean. We model this “nonbelief in the Law of Large Numbers” by assuming that a person believes that proportions in any given sample might be determined by a rate different than the true rate. In prediction, a nonbeliever expects the distribution of signals will have fat tails. In inference, a nonbeliever remains uncertain and influenced by priors even after observing an arbitrarily large sample. We explore implications for beliefs and behavior in a variety of economic settings.     

EXPLAINING GIFT‐EXCHANGE—THE LIMITS OF GOOD INTENTIONS

This paper explores the limitations of intention‐based social preferences as an explanation of gift‐exchange between a firm and a worker. In a framework with one self‐interested and one reciprocal player, gift‐giving never arises in equilibrium. Instead, any equilibrium in a large class of multistage games must involve mutually unkind behavior of both players. Besides gift‐exchange, this class of games also includes moral hazard models and the rotten kid framework. Even though equilibrium behavior may appear positively reciprocal in some of these games, the self‐interested player never benefits from reciprocity. We discuss the relation of these results to the theoretical and empirical literature on gift‐exchange in employment relations.     

REFERENCE POINTS,SOCIAL NORMS,AND FAIRNESS IN CONTRACT RENEGOTIATIONS

How does an ex‐ante contract affect behavior in an ex‐post renegotiation game? We address this question in a canonical buyer–seller relationship with renegotiation. Our paper provides causal experimental evidence that an initial contract has a highly significant and economically important impact on renegotiation behavior that goes beyond the effect of contracts on bargaining threat points. We compare situations in which an initial contract is renegotiated to strategically equivalent bargaining situations in which no ex‐ante contract was written. The ex‐ante contract causes sellers to ask for markups that are 45% lower than in strategically equivalent bargaining situations without an initial contract. Moreover, buyers are more likely to reject given markups in renegotiations than in negotiations. These effects do not depend on whether the contract was written under competitive or monopolistic conditions. Our results provide strong evidence supporting the hypothesis that contracts serve as reference points that shape and coordinate the expectations of the contracting parties.     

COMMUNICATION,COORDINATION, AND NETWORKS

We study experimentally the role of the network structure of pre‐play communication in determination of outcome and behavior in a multiplayer coordination game with conflicting preferences. We explore the trade‐off between the efficiency and equity of coordination outcomes and its link to the network structure of communication. Our results show substantial variations in both efficiency and equity of coordination outcomes across networks. While, as expected, increasing the length of communication improves the chance of successful coordination, it also reduces the asymmetry in the distribution of coordinated outcomes. We identify behaviors that explain variations in the distribution of coordinated outcomes both within and across networks. In all treatments, coordination is mostly explained by convergence in communication.     

REDUCING OVERREACTION TO CENTRAL BANKS' DISCLOSURES: THEORY AND EXPERIMENT

Financial markets are known for overreacting to public information. Central banks can reduce this overreaction either by disclosing information to only a fraction of market participants (partial publicity) or by disclosing information to all participants but with ambiguity (partial transparency). In theory, overreaction can be similarly reduced by either communication strategy. A laboratory experiment shows that both communication strategies succeed in reducing overreaction, though not as much as theory predicts. The opportunity in our information age for central banks to choose between partial publicity and partial transparency to control the market reaction is then discussed.     

EXPONENTIAL‐GROWTH BIAS AND LIFECYCLE CONSUMPTION

Exponential‐growth bias (EGB) is the tendency for individuals to partially neglect compounding of exponential growth. We develop a model wherein biased agents misperceive the intertemporal budget constraint, and derive conditions for overconsumption and dynamic inconsistency. We construct an incentivized measure of EGB in a US‐representative population and find substantial bias, with approximately one third of subjects estimated as the fully biased type. The magnitude of the bias is negatively associated with asset accumulation, and does not respond to a simple graphical intervention.     

DOES THE BETTER‐THAN‐AVERAGE EFFECT SHOW THAT PEOPLE ARE OVERCONFIDENT?: TWO EXPERIMENTS

We conduct two experimental tests of the claim that people are overconfident, using new tests of overplacement that are based on a formal Bayesian model. Our two experiments, on easy quizzes, find that people overplace themselves. More precisely, we find apparently overconfident data that cannot be accounted for by a rational population of expected utility maximizers who care only about money. The finding represents new evidence of overconfidence that is robust to the Bayesian critique offered by Benoît and Dubra (Jean‐Pierre Benoît and Juan Dubra (2011). “Apparent Overconfidence.” Econometrica, 79, 1591–1625). We discuss possible limitations of our results.     

PROPERTY RIGHTS AND THE EFFICIENCY OF BARGAINING

We show that efficient bargaining is impossible for a wide class of economic settings and property rights. These settings are characterized by (i) the existence of “adverse efficient opt‐out types”, whose participation does not change the efficient allocation and who, when they opt out, are the worst type other agents can face, and (ii) non‐existence of the “marginal core”, and its multivaluedness with a positive probability. We also examine the optimal allocation of property rights within a given class that satisfies (i), such as simple property rights, liability rules, and dual‐chooser rules. We characterize property rights that minimize the expected subsidy required to implement efficiency. With two agents, simple property rights that are optimal in this way maximize the expected surplus at the status quo allocation, but this no longer holds with more agents. We also study “second‐best” budget‐balanced bargaining under a liability rule. The optimal “second‐best” liability rule may differ from, but is often close to, the expectation of the victim's harm, which would be optimal if there were no bargaining. However, liability rules that are close to a simple property right result in a lower expected surplus than the simple property right they are near.     

DO LAB EXPERIMENTS MISREPRESENT SOCIAL PREFERENCES? THE CASE OF SELF‐SELECTED STUDENT SAMPLES

Social preference research has received considerable attention among economists in recent years. However, the empirical foundation of social preferences is largely based on laboratory experiments with self‐selected students as participants. This is potentially problematic as students participating in experiments may behave systematically different than nonparticipating students or nonstudents. In this paper we empirically investigate whether laboratory experiments with student samples misrepresent the importance of social preferences. Our first study shows that students who exhibit stronger prosocial inclinations in an unrelated field donation are not more likely to participate in experiments. This suggests that self‐selection of more prosocial students into experiments is not a major issue. Our second study compares the behavior of students and participants recruited from the general population in a trust experiment. In general, we find very similar behavioral patterns for the two groups, but nonstudents make significantly more generous repayments suggesting that results from student samples might be seen as a lower bound for the importance of prosocial behavior.     

SEPARATING MORAL HAZARD FROM ADVERSE SELECTION AND LEARNING IN AUTOMOBILE INSURANCE: LONGITUDINAL EVIDENCE FROM FRANCE

The identification of information problems in different markets is a challenging issue in the economic literature. In this paper, we study the identification of moral hazard from adverse selection and learning about risk within the context of a multi‐period dynamic model. We extend the model of Abbring, Chiappori, and Pinquet (2003, Journal of the European Economic Association, 1, 767–820) to include learning about risk and insurance coverage choice over time. We derive testable empirical implications for panel data. We then perform tests using longitudinal data from France during the period 1995–1997. We find evidence of moral hazard among a sub‐group of policyholders with less driving experience (less than 15 years). Policyholders with fewer than five years of experience have a combination of learning about risk and moral hazard, whereas no residual information problem is found for policyholders with more than 15 years of experience.     

The Effects of Personality Traits on Wages: A Matching Approach

I use the National Longitudinal Survey of Youth 1979 to estimate the effects of adolescent measurements of self‐esteem and locus of control on adult wages using propensity score matching. An adolescent possessing high self‐esteem will experience between 8.5 and 9.2 per cent higher wages as an adult. This result is statistically significant and robust to the addition of cognitive skill and family background characteristics. When cognitive skill and family background characteristics are controlled for, locus of control as an adolescent is insignificant in explaining adult wages. This result is contrary to findings in the literature.     

CATEGORIZE THEN CHOOSE: BOUNDEDLY RATIONAL CHOICE AND WELFARE

We propose a boundedly rational model of choice where agents categorize alternatives before choosing. The model explains some behavioral anomalies, and it is fully characterized by a property of choice data: a categorizer can never exhibit certain patterns of “revealed preference reversals”. This model offers clues on the problem of making welfare judgements in the presence of boundedly rational agents.     

HOW DO INFORMAL AGREEMENTS AND REVISION SHAPE CONTRACTUAL REFERENCE POINTS?

The notion of contracts as reference points provides the basis for a deeper understanding of important phenomena such as the employment contract, vertical integration, firm scope, authority, and delegation. Previous experiments lend support to this notion but they ignore realistic aspects of trading relationships such as informal agreements and ex‐post renegotiation or revision. Here we show that the central behavioral mechanism underlying contractual reference points is robust to such considerations. Our data reveal that informal agreements can mitigate the trade‐off between rigidity and flexibility but they do not fully resolve the problem of misaligned reference points. Our experiments also show that contract revision is a more nuanced process than the previous literature has recognized. We find, for example, that it is sometimes better for parties to write a simple (rigid) contract and then revise it ex post if needed, rather than to anticipate and include future contingencies in a (flexible) contract from the outset.