Applied Stichastics/ Math Biology Seminar: Christian Hilbe

Indirect reciprocity explores how humans act when their reputation is at stake. The corresponding models describe how reputations change over time, depending on the actions people take, and on the social norms they employ. The first part of the talk gives a brief overview of the field. It discusses how the reputation dynamics within a population can be modelled mathematically, and which social norms have been proposed to stabilize cooperation in the long run. The second part shows that these previously proposed norms fail once the models take into account that information is typically private and noisy. Finally, we prove in the last part that cooperation can be sustained in noisy environments if individuals have access to stochastic norms.