Marie-Claire Villeval

French National Centre for Scientific Research | CNRS · UMR GATE - Groupe d’Analyse et de Théorie Economique

How do we assess the veracity of ambiguous news, and does metacognition guide our decisions to seek further information? In a controlled experiment, participants evaluated the veracity of ambiguous news and decided whether to seek extra information. Confidence in their veracity judgments did not predict accuracy, showing limited metacognitive abili...

We experimentally investigate how players with opposing views compete for influence through strategic targeting in networks. We varied the network structure , the relative influence of the opponent, and the heterogeneity of the nodes' initial opinions. Although most players adopted a best-response strategy based on their relative influence, we also...

Working for a firm engaged in Corporate Social Responsibility (CSR) appeals to potential workers by boosting their self-image and sense of purpose. We propose an additional mechanism: CSR signals a firm's future treatment of workers. Our model links CSR engagement with a firm's propensity to support workers during unforeseen times of need. Under th...

Although they usually manage to combine information to make well-informed decisions, groups also make mistakes. We investigate experimentally one source of sub-optimal decision-making by groups: the selective and asymmetric sharing of ego-relevant information within teams. We show that good news about one's performance is shared more often with tea...

The mechanisms by which individuals evaluate the veracity of uncertain news and subsequently decide whether to seek additional information to resolve uncertainty remain unclear. In a controlled experiment participants assessed non-partisan ambiguous news and made decisions about whether to acquire extra information. Interestingly, confidence in the...

We investigated lying as a collective‐risk social dilemma. Misreporting resulted in increased individual earnings but when total claims reached a certain threshold, all group members were at risk of collective sanction, regardless of their individual behavior. Due to selfishness and miscoordination, most individuals earned less than the reservation...

We experimentally study the social transmission of “inconvenient” information about the externalities generated by one's own decision. In the laboratory, we pair uninformed decision makers with informed senders. Compared to a setting where subjects can choose their information directly, we find that social interactions increase selfish decisions. O...

We use a laboratory experiment to understand the channels through which honesty oaths can affect behavior and credibility. Using a game with asymmetric information in a financial market setting that captures some important features of advisor-investor interactions, we manipulate the common knowledge of the promise and investigate three non-pecuniar...

We study the impact of competition on morals using a dynamic variant of the die-under-the-cup task. Players can repeatedly misreport the outputs of consecutive die rolls to earn more money, either under an individual piece-rate pay scheme or in a two-player tournament. In this dynamic setting, we disentangle the effect of the incentive scheme and t...

In the future, artificially intelligent algorithms will make more and more decisions on behalf of humans that involve humans’ social preferences. They can learn these preferences through the repeated observation of human behavior in social encounters. In such a context, do individuals adjust the selfishness or prosociality of their behavior when it...

We examine the educative role played by parents in social norm transmission. Using a field experiment, we study whether parents enforce and comply more with norms when their children are present compared to when they are not. We compare similar parents when or after they bring or pick up their children at school. We find that parents accompanying c...

In a finitely repeated game with asymmetric information, we experimentally study how individuals adapt the nature of their lies when settings allow for reputation building. Although some lies can be detected ex post by the uninformed party, others remain deniable. We find that traditional market mechanisms, such as reputation, generate strong chang...

If individuals tend to behave like their reference group, is it because of peer effects, self-selection, or both? Using a peer effect model allowing for conformity and link formation, we designed a real-effort laboratory experiment in which individuals could misreport their performance and select their peers. Our results reveal both a preference fo...

Exploring the joint dynamics of laws and social norms helps understand when social norms are sticky or adaptive. Using the example of the social and physical distancing measures introduced to contain the COVID-19 pandemic in 2020, we studied whether introducing, and then lifting, distancing regulations led individuals to quickly change their habits...

Deterrence institutions are widely used in modern societies to discourage rule violations but whether they have an impact beyond their immediate scope of application is usually ignored. Using a quasi-experiment with naturally occurring variation in inspections we found evidence of spillover effects across contexts. We identified fraudsters and non-...

We present experiments exploring why high ability workers join teams with less able coworkers when there are no short-term financial benefits. We distinguish between two explanations: prosocial preferences and expected long-term financial gains from teaching future teammates. Participants perform a real-effort task and decide whether to work indepe...

We study a dynamic variant of the die-under-the-cup task where players can repeatedly misreport the outcomes of consecutive die rolls to earn more money, either under a non-competitive piece rate scheme or in a two-player competitive tournament. In this dynamic setting we test (i) whether giving continuous feedback (vs. final ex post feedback) on t...

Editor's Note: this Article has been retracted; the Retraction Note is available at https://doi.org/10.1038/s41598-020-80528-2 .

We explore the effects of competitive incentives and of their time horizon on the evolution of both asset prices and trading activity in experimental asset markets. We compare (i) a no-bonus treatment; (ii) a short-term bonus treatment in which bonuses are assigned to the best performers at the end of each trading period; (iii) a long-term bonus tr...

Achieving an ambitious goal frequently requires succeeding in a sequence of intermediate tasks, some being critical for the final outcome, and others not. However, individuals are not always able to provide a level of effort sufficient to guarantee success in all such intermediate tasks. The ability to manage effort throughout the sequence of tasks...

Significance Using large-scale incentivized online experiments, we tested two possible origins of individuals’ forgetting about their past cheating behavior in a mind game. We found that purely hedonic considerations, such as the maintenance of a positive self-image, are not sufficient to motivate unethical amnesia, but the addition of an instrumen...

The role of testosterone on cognitive functions in humans remains controversial. One recent hypothesis suggests that this steroid hormone advances social status. As being observed by others is known to modulate a range of behaviors because of image concerns, we hypothesized that such an audience effect might be an important component of status seek...

In response to the pandemic of COVID-19 and in lack of pharmaceutical solutions, many countries have introduced social and physical distancing regulations to contain the transmission of the virus. These measures are effective insofar as they are able to quickly change people's habits. This is achieved by changing the monetary incentives of rule vio...

There is evidence that human decision-making is affected by current body energy levels and physiological states. There is less clear evidence linking decision-making to long-term changes in energy, as those associated with obesity. We explore the link between energy, obesity and dishonesty by comparing the behaviour of obese and lean subjects when...

Does feedback on success in a task increase individuals' beliefs about their chance to succeed in a subsequent, unrelated, task? Does feedback on failure have a symmetric effect? Is the distortion of beliefs, possibly due to motivated beliefs, mistakes in updating or the feeling of having a lucky day, heterogeneous across individuals, in particular...

We consider the external validity of laboratory measures of risk attitude. Based on a large-scale experiment using a representative panel of the Dutch population, we test if these measures can explain two different types of behavior: (i) behavior in laboratory risky financial decisions, and (ii) behavior in naturally-occurring field behavior under...

A donation may have ambiguous costs or ambiguous benefits. Behavior in a laboratory experiment suggests that individuals use this ambiguity strategically as a moral wiggle room to act less generously without feeling guilty. Such excuse-driven behavior is more pronounced when the costs of a donation -rather than its benefits- are ambiguous. However,...

La théorie du crime de Gary Becker a été mise à mal par une accumulation de preuves expérimentales qui ont mis en évidence une aversion intrinsèque des agents économiques au mensonge et l’importance de leurs croyances sur la perception de leur conduite morale par autrui. Cherchant à préserver leur réputation et leur image quand leurs actes génèrent...

Plusieurs études montrent que les préoccupations d’image sociale stimulent les comportements prosociaux. Nous étudions un contexte dans lequel il existe une incertitude sur l’action qui est prosociale. La quête d’une meilleure image sociale entre alors potentiellement en conflit avec le comportement prosocial. Ce conflit peut induire un « mauvais »...

In a laboratory experiment we test the interaction effects of group identity and status on interpersonal trust. Natural group identity is generated by school affiliation. Status (expert or agent) is awarded based on the relative performance in a math quiz that is ex ante less favorable to the subjects from one group. We find that “promoted” trustor...

Humans not only value extrinsic monetary rewards but also their own morality and their image in the eyes of others. Yet violating moral norms is frequent, especially when people know that they are not under scrutiny. When moral values and monetary payoffs are at odds, how does the brain weigh the benefits and costs of moral and monetary payoffs? He...

The memory people have of their past behavior is one of the main sources of information about themselves. To study whether people retrieve their memory self-servingly in social encounters, we designed an experiment in which participants play binary dictator games and then have to recall the amounts allocated to the receivers. We find evidence of mo...

We investigate whether peer effects at work differ by gender and whether the differences -if any- depend on work organization. We develop a social network model with gender heterogeneity that we test using a real-effort laboratory experiment. We compare unidirectional networks (with a one-way information flow) and bidirectional networks (with a two...

Psychological game theory can contribute to renew the analysis of unethical behavior by providing insights on the nature of the moral costs of dishonesty. We investigate the moral costs of embezzlement in situations where donors need intermediaries to transfer their donations to recipients and where donations can be embezzled before they reach the...

Using a real-effort experiment, we study whether group identity affects unethical behavior in a contest game. We vary whether minimal group identity is induced or not, whether individuals have to report their own outcome or the outcome of their competitor, and whether pairs of competitors share the same group identity or not. We show that individua...

In the presence of social dilemmas, cooperation is more difficult to achieve when populations are heterogeneous because of conflicting interests within groups. We examine cooperation in the context of a nonlinear common pool resource game, in which individuals have unequal extraction capacities and have to decide on their extraction of resources fr...

In a laboratory experiment we test the interaction effects of group identity and status on interpersonal trust. Natural group identity is generated by school affiliation. Status (expert or agent) is awarded based on the relative performance in a math quiz that is ex ante less favorable to the subjects from one group. We find that “promoted” trustor...