With links to replication materials (OSF page) where available.

  • Self-Persuasion: Evidence from field experiments at international debating competitions, with Egon Tripodi and Peter SchwardmannAmerican Economic Review, 2022, 112 (4): 1118-46.
    [.pdf]     Journal page     OSF page    Abstract
    Laboratory evidence shows that when people have to argue for a given position, they persuade themselves about the position’s factual and moral superiority. Such self-persuasion limits the potential of communication to resolve conflict and reduce polarization. We test for this phenomenon in a field setting, at international debating competitions that randomly assign experienced and motivated debaters to argue one side of a topical motion. We find self-persuasion in factual beliefs and confidence in one’s position. Effect sizes are smaller than in the laboratory, but robust to a one-hour exchange of arguments and a ten-fold increase in incentives for accuracy.
  • Casting doubt: Image concerns and the communication of social impact, with Manuel FoersterEconomic Journal, 2021, 131: 2887–2919. 
    [.pdf]     Journal page     OSF page    Abstract
    We investigate strategic communication about the social impact of costly prosocial actions. A ‘sender’ with noisy information about impact sends a cheap-talk message to a ‘receiver’, upon which both agents choose whether to act. In the presence of social preferences and image concerns, the sender trades off persuasion, exaggerating impact to induce receiver action, and justification, downplaying impact to cast doubt on the effectiveness of action and excuse her own passivity. In an experiment on charitable giving we find evidence for both motives. In line with our theory and a justification motive, increasing image concerns reduces communication of positive impact.

    Older version with more general model: Denial and alarmism in collective action problems, TI working paper 019/2018.

  • Overconfidence and gender gaps in redistributive preferences: Cross-Country experimental evidence,  with Thomas BuserGianluca Grimalda and Louis Putterman, Journal of Economic Behavior and Organization, 2020, 178, 267–286. 
    [.pdf]     Journal page     Abstract
    Gender differences in voting patterns and political attitudes towards redistribution are well-documented. The experimental gender literature suggests several plausible behavioral explanations behind these differences, relating to gender differences in confidence concerning future relative income position, risk aversion, and social preferences. We use data from lab experiments on preferences for redistribution conducted in the U.S. and several European countries to investigate gender differences and their causes. On aggregate, women’ s demand for redistribution is higher than men’ s, but the differences vary considerably across locations and countries. Moreover, the gender difference appears only when the source of inequality is based on relative abilities, but not when it is based on luck. Our most robust finding is that across all sampled locations, men’ s relatively higher (over)confidence in their abilities, in comparison to women, leads them to specify lower redistribution levels. We discuss the role of confidence in accounting for gender differences in political and redistributive choices outside the lab.

    Blogs: Psychology TodayOECD Development MattersESB

  • Bracelets of pride and guilt? An experimental test of self-signaling, with Ferdinand von Siemens, Journal of Economic Behavior and Organization, 2020, 172, 280-91
    [.pdf]     Journal page      OSF page    Abstract
    Self-signaling theory argues that behavior is important to build up or maintain a favorable self-image. We provide a novel test of this argument by manipulating the importance of behavior for future self-image. In two experiments, part of the subject pool is incentivized to wear bracelets as reminders of their initial identity-relevant behavior. We find some evidence that the bracelets increase anticipated memory, which should make behavior more relevant for managing a positive self-image. However, we find no evidence for self-signaling. Instead, our results suggest that participants resolve cognitive dissonance by constructing self-serving rationalizations of their actions that serve as cheap substitutes for self-signaling.

  • Deception and Self-Deception, with Peter SchwardmannNature Human Behaviour, 2019, 3:10, 1055-61.
    [.pdf]     Journal page     OSF page    Abstract
    There is ample evidence that the average person thinks he or she is more skilful, more beautiful and kinder than others and that such overconfidence may result in substantial personal and social costs. To explain the prevalence of overconfidence, social scientists usually point to its affective benefits, such as those stemming from a good self-image or reduced anxiety about an uncertain future. An alternative theory, first advanced by evolutionary biologist Robert Trivers, posits that people self-deceive into higher confidence to more effectively persuade or deceive others. Here we conduct two experiments (combined n = 688) to test this strategic self-deception hypothesis. After performing a cognitively challenging task, half of our subjects are informed that they can earn money if, during a short face-to-face interaction, they convince others of their superior performance. We find that the privately elicited beliefs of the group that was informed of the profitable deception opportunity exhibit significantly more overconfidence than the beliefs of the control group. To test whether higher confidence ultimately pays off, we experimentally manipulate the confidence of the subjects by means of a noisy feedback signal. We find that this exogenous shift in confidence makes subjects more persuasive in subsequent face-to-face interactions. Overconfidence emerges from these results as the product of an adaptive cognitive technology with important social benefits, rather than some deficiency or bias.

    Blog posts: Psychology TodayNature ResearchDarwinian BusinessFehrAdviceImperfect Cognitions.
    Media: ABC NewsFAZFoliaMSNWirtschaftswochePhys.orgSüddeutsche Zeitung.

  • On esteem-based incentives, with Ali Mazyaki, International Review of Law Economics, 2019, 60, 105848.
    [.pdf]     Journal page     Abstract
    The rise of the internet, increased connectivity and higher availability of personal data increases the rele-vance of incentives based on reputation and the allocation of esteem. However, their use is controversial:critics argue that shaming can lead to a loss of control over the size of the sanction and to mob justice. Weuse the signaling model of social behavior by Bénabou and Tirole (2011) to explore the effect of esteem-based incentives and their interaction with traditional fines. We show that the use of esteem and stigmacan indeed lead to a loss of control by generating multiple equilibria, some of which feature high levels ofcompliance and high levels of stigma. Moreover, the deterrent effect of monetary and esteem incentivesis interdependent. If both types of incentives are costly to implement, esteem incentives should optimallybe used relatively more for rare behaviors and in societies that have more heterogeneous values.

  • Peer effects and risk sharing in experimental asset markets , with Paul Gortner, European Economic Review, 2019, 116, 129-147
    [.pdf]     Journal page     OSF page     Abstract
    We investigate the effect of introducing information about peer portfolios in an experi- mental Arrow–Debreu economy. Confirming the prediction of a general equilibrium model with inequality averse preferences, we find that peer information leads to reduced vari- ation in payoffs within peer groups. Information also improves risk sharing, as the data suggests that experiencing earnings deviations from peers induces a shift to more balanced portfolios. In a treatment where we highlight the highest earner, we observe a reduction in risk sharing, while highlighting the lowest earner has no effects compared to providing neutral information. Our results indicate that the presence of social information and its framing is an important determinant of equilibrium in financial markets.

  • Responsiveness to feedback as a personal trait , with Thomas Buser and Leonie GerhardsJournal of Risk and Uncertainty, 2018, 56:2, 165-192.
    [.pdf]     Journal page     Abstract
    We investigate individual heterogeneity in the tendency to under-respond to feedback (“conservatism”) and to respond more strongly to positive compared to negative feedback (“asymmetry”). We elicit beliefs about relative performance after repeated rounds of feedback across a series of cognitive tests. Relative to a Bayesian benchmark, we find that subjects update on average conservatively but not asymmetrically. We define individual measures of conservatism and asymmetry relative to the average subject, and show that these measures explain an important part of the variation in beliefs and competition entry decisions. Relative conservatism is correlated across tasks and predicts competition entry both independently of beliefs and by influencing beliefs, suggesting it can be considered a personal trait. Relative asymmetry is less stable across tasks, but predicts competition entry by increasing self-confidence. Ego-relevance of the task correlates with relative conservatism but not relative asymmetry.

  • Self-image and willful ignorance in social decisions, with Zachary Grossman, Journal of the European Economic Association, 201715:1, 173-217.
    [.pdf]     Journal page     Abstract
    Avoiding information about adverse welfare consequences of self-interested decisions, or willful ignorance, is an important source of socially harmful behavior. To understand this issue, we analyze a Bayesian signaling model of an agent who cares about self-image and has the opportunity to learn the social benefits of a personally costly action. We show that willful ignorance can serve as an excuse for selfish behavior by obfuscating the signal about the decision-maker’s preferences, and help maintain the idea that the agent would have acted virtuously under full information. We derive several behavioral predictions that are inconsistent with either outcome-based preferences or social-image concern and conduct experiments to test them. Our findings, as well as a number of previous experimental results, offer support for these predictions and thus, the broader theory of self-signaling.

    Media:  Summary blogpost at Oxford University Press.

  • Dual-Process Reasoning in Charitable Giving: Learning from Non-results, with Zachary Grossman,  Games, 2017, 8:3, 36-49. 
    [.pdf]     Journal page     Abstract
    To identify dual-process reasoning in giving, we exposed experimental participants making a charitable donation to vivid images of the charity’s beneficiaries in order to stimulate affect. We hypothesized that the effect of an affective manipulation on giving would be larger when we simultaneously put the subjects under cognitive load using a numerical recall task. Independent treatment checks reveal opposite responses in men and women and cast some doubt on the reliability of our mainstream treatment manipulations and assessment tools. We find no evidence for dual-process decision-making, even among women, whose responses to the manipulations conformed most to our expectations. These results highlight the need for caution in the use of these common manipulations, the importance of independent manipulation checks, and the limitations of dual-process models for understanding altruistic behavior. 

  • A method to elicit beliefs as most likely intervals, with Karl SchlagJudgment and Decision Making, 2015, 10:5, 456-468. 
    [.pdf]     Journal page     Abstract
    We show how to elicit the beliefs of an expert in the form of a “most likely interval”, a set of future outcomes that are deemed more likely than any other outcome. Our method, called the Most Likely Interval elicitation rule (MLI), asks the expert for an interval and pays according to how well the answer compares to the actual outcome. We show that the MLI performs well in economic experiments, and satisfies a number of desirable theoretical properties such as robustness to the risk preferences of the expert.

    Earlier version with more theoretical results: Incentives for Eliciting Confidence Intervals.

  • A penny for your thoughts: A survey of methods for eliciting beliefs, with James Tremewan and  Karl SchlagExperimental Economics, 2015, 18:3, 457-490. 
    [.pdf]     Journal page     Abstract
    Incentivized methods for eliciting subjective probabilities in economic experiments present the subject with risky choices that encourage truthful reporting. We discuss the most prominent elicitation methods and their underlying assumptions, provide theoretical comparisons and give a new justification for the quadratic scoring rule. On the empirical side, we survey the performance of these elicitation methods in actual experiments, considering also practical issues of implementation such as order effects, hedging, and different ways of presenting probabilities and payment schemes to experimental subjects. We end with a discussion of the tradeoffs involved in using incentives for belief elicitation and some guidelines for implementation.

  • Preferences for redistribution and perception of fairness: an experimental study, with Ruben Durante and Louis Putterman, Journal of the European Economic Association, 2014, 12:4, 1059-1086.
    [.pdf]     Journal page     Abstract
    We conduct a laboratory experiment to study how demand for redistribution of income depends on self-interest, insurance motives, and social concerns relating to inequality and efficiency. Our choice environments feature large groups of subjects and real-world framing, and differ with respect to the source of inequality (earned or arbitrary), the cost of taxation to the decision maker, the dead-weight loss of taxation, uncertainty about own pretax income, and whether the decision maker is affected by redistribution. We estimate utility weights for the different sources of demand for redistribution, with the potential to inform modeling in macroeconomics and political economy.

  • Resisting moral wiggle room: how robust is reciprocal behaviour?, with Julija Kulisa, Michael Kosfeld and Guido FriebelAmerican Economic Journal: Microeconomics, 2014, 6:3, 256-64. 
    [.pdf]     Journal page     Abstract
    We provide the second mover in a trust game and a moonlighting game with an excuse for not reciprocating. While this type of manipulation has been shown to strongly reduce giving in the dictator game, we find that the availability of the excuse has no effect on the incidence of reciprocal behavior in these games. Our results cast doubt on the generalizability of previous dictator game findings and suggest that image concerns are not a key driver of reciprocal behavior.

  • Eliciting probabilities, means medians, variance and covariances without assuming risk neutrality, with Karl SchlagTheoretical Economics Letters, 2013, 3:1, 38-42.
    [.pdf]     Journal page     Abstract
    We are interested in incentivizing experimental subjects to report their beliefs truthfully, without imposing assumptions on their risk preferences. We prove that if subjects are not risk neutral, it is not possible to elicit subjective probabilities or the mean of a subjective probability distribution truthfully using deterministic payments schemes, which are predominant in the literature. We present a simple randomization trick that transforms deterministic rewards into randomized rewards, such that agents with arbitrary risk preferences report as if they were risk neutral. Using this trick, we show how to elicit probabilities, means, medians, variances and covariances of the underlying distribution without assuming risk neutrality.

  • Sanctions that signal: an experiment, with Roberto Galbiati and Karl Schlag, Journal of Economic Behavior and Organization, 2013, 94, 34-51. 
    [.pdf]     Journal page     Abstract
    The introduction of sanctions provides incentives for more pro-social behavior, but may also be a signal that non-cooperation is prevalent. In an experimental minimum-effort coordination game we investigate the effects of the information contained in the choice to sanction. We compare the effect of sanctions that are introduced exogenously by the experimenter to that of sanctions which have been actively chosen by a subject who has superior information about the previous effort of the other players. We find that cooperative subjects perceive actively chosen sanctions as a negative signal which significantly reduces the effect of sanctions.

  • Status-Seeking in Criminal Subcultures and the Double Dividend of Zero-Tolerance, with Robert DurJournal of Public Economic Theory, 2013, 15:1, 77-93. 
    [.pdf]     Journal page     Abstract
    This paper offers a new argument for why a more aggressive enforcement of minor offenses (zero-tolerance) may yield a double dividend in that it reduces both minor offenses and more severe crime. We develop a model of criminal subcultures in which people gain social status among their peers for being “tough” by committing criminal acts. As zero-tolerance keeps relatively “gutless” people from committing a minor offense, the signaling value of that action increases, which makes it attractive for some people who would otherwise commit more severe crime. If social status is sufficiently important in criminal subcultures, zero-tolerance reduces crime across the board.

  • The signaling power of sanctions in social dilemmas, Journal of Law, Economics and Organization, 2012, 28:1, 103-25.
    [.pdf]     Journal page     Abstract
    Evidence from field and laboratory experiments indicates that a large fraction of the people behave like conditional cooperators in public good games. In this article, I investigate the implications of the existence of both conditional cooperators and egoists for optimal law enforcement strategies. When norms of cooperation exist between conditional cooperators, sanctions set by an authority can be lower than in a “Hobbesian” setting where everybody is egoistic. Moreover, if the authorities have private information about the fraction of egoists in society, low sanctions can be optimal because they signal that there are few defectors and thus “crowd in” trust and cooperation between agents. In social dilemmas where conditional cooperation is an important factor, as is the case in tax compliance, the model provides a rationale for the low observed sanctions in the real world and the mixed evidence on the effectiveness of deterrence.

  • Beyong the state of nature: Introducing social interactions in the economic model of crime, Review of Law & Economics, 2012, 8:1, 401–32.
    [.pdf]     Journal page     Abstract
    The standard economic model of crime emphasizes the individual rationality and agency of criminals, while sociological theories typically emphasize the importance of social forces. This essay surveys a recent strand of literature on law enforcement that bridges these two approaches. Using the tools of game theory, it investigates crime as the outcome of the interaction between rational individuals. The survey shows that this analysis leads to a substantially richer set of hypotheses regarding the effect of enforcement than the standard economic model, depending on the classification of the social context, or game, in which agents operate. In doing so, it brings rational choice theories in line with long-standing insights in the field of criminology, as well as providing new analytical distinctions and generalizations.

Book chapters, encyclopedia entries

  • The broken window effect, with Mataka Flynn and Rogier van der Wolk. Encyclopedia of Law and Economics, 2017.Do small signs of neighborhood disorder lead to crime?
  • The Ecological and Economic Conditions of Exploitation Strategies. 
    Burton-Chellew, M., Kacelnik, A., Arbilly, M., dos Santos, M., Mathot, K.M., McNamara, J.M., Mengel, F., van der Weele, J. and Vollan, B. 2017. In:Investors and Exploiters in Ecology and Economics: Principles and Applications, edited by L-A. Giraldeau, P. Heeb, and M. Kosfeld. Strüngmann Forum Reports, vol. 21 J. Lupp, series editor. Cambridge, MA: MIT Press