Research

The power of leadership in changing social norms in heterogeneous societies with Marie Claire Villeval and Fabio Galeotti, Proceedings of the National Academy of Sciences,123(13), e2526916123.

Changing a social norm is complex even when the norm has become detrimental for the society notably because individuals have a strong pressure to conform to it. We investigated experimentally whether a leader can accelerate or delay such a change through their recommendations by coordinating the expectations of individuals, and whether this depends on the leader’s own preference and leadership style. Building on the dynamic setting introduced by Andreoni et al. (2021) we confirm that norms are sticky in the absence of any coordination device. We show that leaders are remarkably successful in moving the society to a more efficient norm, regardless of the speed at which their own and the society’s preferences evolve. However, normative change happens slower or faster depending on whether the leade prioritizes their own preference or the preferences of the majority. In a follow-up experiment we show that introducing imperfect communication among citizens induces leaders to consider more the preferences of the majority of the society when recommending a normative action.

Solving Normative Conflicts in Collective Action by Promoting Redistribution with Marie Claire Villeval and Lata Gangadharan  (WP)

Heterogeneous returns from contributions to a public good create a normative conflict between equality and efficiency. In a laboratory experiment, we proposed an indicative menu of contribution principles including one featuring a decentralized redistribution mechanism ensuring earnings equality in exchange for fully efficient contributions. Although a majority of individuals, when in the position of an impartial observer, considered this principle to be the most appropriate and expected others to agree, they failed to act on it. Designating a leader who endorsed this principle and made non-binding recommendations enabled a majority of groups to adopt it successfully. This resulted in full contributions and earnings equalization through redistribution from advantaged to disadvantaged members, effectively resolving the conflict.

Political tribalism and voter preferences with Fabio Galeotti and Daniel Zizzo

The identification of electors with the candidates in public elections can sway their decision either towards or against a candidate. We investigate whether and to what extent electors are willing to sacrifice the quality of their representatives in public elections for their political identification. In Experiment 1, we introduce a trade-off between the competence and the political closeness between two candidates. We find that electors tend to have a bias towards candidates who share a similar political identity as theirs even if this results in a loss in profit. No such bias is observed when the trade-off is between competence and art identity. To test whether the observed in-group bias translates to other real identities such as sports, we ran a second experiment in which we compared the political identification bias to that of a sport identification. We find that the political bias is still present. Sport preferences also induce a bias in voting decisions, but to a lower extend.

Using Social Norms to Promote Charitable Giving and Volunteering with Joris Schroder and Robert Smith

Prosocial behaviours such as charitable giving and volunteering are often underprovided because they impose personal costs while benefiting unknown and unrelated others. In a between-subject laboratory experiment, we test the effectiveness of two scalable social-norm interventions in promoting prosocial behaviour: (i) social information nudges and (ii) “Giving More Together”. We compare the effects of these interventions on charitable giving and volunteering, and examine the mechanisms through which they operate by measuring personal norms, social expectations, and social preferences.

Cooperating Beyond Group Boundaries with Joris Schroder and Simon Gächter

Human social life is fundamentally structured by group membership and identity. While shared identity can foster within-group cooperation, it may undermine cooperation across group boundaries. This tension is increasingly relevant in the context of rising polarization, given that addressing global challenges such as climate change requires cooperation beyond group boundaries. This project investigates how group identity affects cooperation in a repeated threshold public goods game. Across five treatments, we vary the type of group identity, ranging from no identity to minimal identity to real-world identities (e.g., nationality). We further manipulate whether similarities or differences between subgroups are emphasized.To identify the mechanisms underlying cooperation, we elicit social preferences, personal norms, and second-order beliefs about others’ contributions, as well as conditional contribution strategies.