Research

Inequality, Social Norms and Cooperation: Strategy Choice in the Infinitely Repeated Prisoners' Dilemma

Teyssier, S., & Wieczorek, B. (2025). Inequality, social norms and cooperation: Strategy choice in the infinitely socially iterated prisoner’s dilemma. Journal of Economic Behavior & Organization, 229, 106819.

​Societies today face important challenges related to cooperation, which is needed among individuals who interact at a nonregular frequency. In this context, cooperation can be sustained if social norms push in this direction. We design an online experiment in which participants make strategic choices in an infinitely socially iterated prisoner’s dilemma. We examine the effects of inequality on social norms of cooperation and how norm compliance, in turn, affects cooperation. Inequality exists when two participants defect and cooperation gives equal payoffs in one treatment or keeps the unequal payoffs in the other. The results show that inequality weakens social norms by limiting first- and second-order normative beliefs about cooperation as well as descriptive beliefs about the other participants’ cooperation. Inequality reduces the likelihood of cooperation mainly driven by the change in social norms. Overall, the mere existence of inequality causes these changes, not specific behaviors, depending on the participants’ type.  

Dynamic information provision for household water consumption

Wieczorek B. - Submitted.

​Evidence of the effectiveness of social norms information in increasing pro-social and pro-environmental behavior has been widely reported in the literature and by policy-makers. Static information on social norms has proved effective in influencing marginalized individuals in the areas of water, energy, and others.

In this study, I developed a field experiment on household water consumption by implementing a new information policy based on the literature on dynamic norms to influence average individuals, who represent the majority. Dynamic information exploits the spread of pro-social or pro-environmental behaviors in order to promote them.

Results show a significant effect of dynamic information on below-average households, with a reduction of over 20% of water consumption. Yet their effectiveness disappears over time, suggesting their potential is fully exploited on specific occasions, such as a temporary drought. Finally, I explore explanations for the effectiveness or ineffectiveness of the different information provided by cognitive and psychological processes.

Proenvironmental behavior dynamics in polarized populations 

Wieczorek B., Ferrière R. - Submitted.

In the face of global environmental challenges, proenvironmental action remains limited in scope and scale. Identifying robust pathways to behavioral change is difficult due to the intricate interplay of individual, social, and environmental factors. We present a behavior-environment feedback model to evaluate the roles that key individual (attitudes), social (descriptive and normative expectations), and environmental (experience) factors play in promoting or hindering the adoption of a costly proenvironmental behavior in polarized populations comprised of 'environment-aware' and 'environment-brush off' individuals.  With polarization, the risk of a vicious 'green gap', whereby environment-aware individuals actually underperform, is widespread. Yet the green gap can be closed and a 'green act' situation, whereby individuals' behavior and attitude align, can be achieved, depending on the weight of descriptive expectations and the strength of environmental sensitivity in the decision-making process. To boost the spread of proenvironmental action and achieve a virtuous green gap whereby environment-brush off individuals tend to overperform, the environment-aware group should be the majority, and normative expectations must strongly influence the decision process. A general requirement for the spread of proenvironmental behavior is that the environment-aware group be the main focus of individuals when they form their descriptive and normative expectations. Our model enables simulations of contrasted policy interventions, allowing direct comparisons between behavioral and monetary approaches and highlighting the need to tailor the scope and implementation scheme of interventions to the unique characteristics of the social and environmental context of specific populations.

Social Tipping Condition on Coordination Games

Tavoni A., Wieczorek B. - Submitted.

​Effective climate change mitigation to avert catastrophic consequences requires a rapid and widespread transition from existing societal and economic baselines to more sustainable and virtuous equilibria. Despite the identification of multiple pathways, large-scale global transitions have yet to materialize.

To investigate the role of human biases in shaping these transitions, we develop an experimental framework capturing both the endogenous emergence of an initial equilibrium and its transition toward a more efficient one. This study focuses on the most fundamental cases, coordination scenarios wherein individual interests align toward a shared objective, investigating the impact of group size and payoff structures, weighing either mainly on pairwise or group coordination. While utility maximization of earnings predicts equivalent coordination and transition behaviors across treatments, we examine the role of social norms and individual behavior as mechanisms moderating our experimental condition.

Increasing group size negatively impacts transitions through two converging mechanisms. First, it inhibits the early emergence of shared norms, thereby weakening initial group coordination, which restricts transitions. Second, it exerts an additional direct negative effect on transitions. Modifying the payoff structure toward pairwise coordination negatively impacts transitions through two diverging mechanisms. First, it alters individual coordination behavior, thereby enhancing initial coordination, which facilitates transitions. However, a second direct negative impact on transitions counteracts this effect. Finally, combining the two conditions produces an additional direct positive effect on transitions, without altering the abovementioned mechanisms. Our study highlights the pivotal influence of interaction and community characteristics on transition dynamics, offering insights into environmental policies.

Social Norms and Community Enforcement of Cooperation

Teyssier S, Wieczorek B. - To be submitted.

Sharing Energy Resources

Llerena D., Roussillon B., Rouchouze O., Pizziol V., Wieczorek B., Fadhuile A., et al.

Complementarity and Agency in Shaping Environmental Action

Pizziol V., Wieczorek B.