Invited talk by Giulia Andrighetto: Norm change and cooperation under collective risk in a long-term experiment

Social norms are a crucial part of the solution to our most pressing societal challenges, from mitigating climate change to reducing the spread of infectious diseases. Despite their relevance, how norms shape cooperation among strangers is still insufficiently understood. Influential theories suggest that the level of exogenous threats faced by different societies plays a key role in the strength of the norms that different cultures have evolved. Still causal evidence of exogenous threats on norms has not been so far collected. Here we deal with this dual challenge using a 30-day collective-risk social dilemma experiment to observe and measure norm change in a controlled setting. We ask whether a looming but uncertain collective catastrophe changes the strength of the social norms of cooperation that may avert it. We find that social norms predict cooperation and causally affect behavior. We also provide the first empirical demonstration that higher risk spontaneously lead to stronger social norms and that, when the risk changes, stronger social norms are more resistant to erosion. Still, the foreseeable loosening of norms in low risk settings has important policy implications. Taken together, our results demonstrate the causal effect of social norms in promoting cooperation and their role in making behavior resilient in the face of exogenous change.

Giulia Andrighetto is a senior researcher at the Institute of Cognitive Sciences and Technologies of the National Research Council of Italy in Rome, where she is the coordinator of the Laboratory of Agent Based Social Simulation  (LABSS). She is also a senior researcher at Mälardalen University, Västerås, Sweden and at the Institute for Future Studies, Stockholm, Sweden. Her research focuses on the emergence, enforcement, change and decay of social norms and their effects on cooperation and conflicts. Her research topics include cooperation, altruism, honesty, as well as bad norms and misinformation. Giulia Andrighetto uses theoretical and computational models, combined with on-line and laboratory experiments, surveys and big data to answer these and related questions about social norms. Although primarily fundamental, her research aims also at informing policy.