Date/Time
Date(s) - 27/09/2023
11:30 am - 12:30 pm

Hans-Theo Normann,  Professor at Heinrich-Heine-Universität Düsseldorf, will present to our economics graduate students and faculty on Wednesday, September 27, in KTH 334!

Hans-Theo is a Professor of Game Theory and Experimental Economics at the Düsseldorf Institute for Competition Economics (DICE). He will be presenting the paper, “Cooperation in Multiplayer Dilemmas“.

Alex’s research focuses on behavioral and experimental economics with a particular interest in studying both paternalistic behaviour and gender differences in beliefs and preferences. She will be presenting the paper “Paternalistic Persuasion“.

Abstract

We analyze infinitely repeated multiplayer prisoner’s dilemmas in continuous-time experiments. As the number of players changes, our design keeps the payoffs of the all-defection, all-cooperation, and unilateral-defection and -cooperation outcomes constant, thus controlling for the minimum discount factor required for cooperation to be an equilibrium. For all group sizes, we study three different variants of the prisoner’s dilemma. In further treatments, we allow actions to be chosen from a continuous set.
We find that cooperation rates decrease with the number of players, a result that we can attribute to the increased strategic uncertainty in larger groups. The different payoff matrices also affect cooperation, and their effects are noticeable even in groups with larger numbers of players. Both group size and payoff effects become stronger with experience in later supergames. The availability of a continuous action set strongly reduces cooperation rates. Strategy frequency estimates suggest that the proportion of defective strategies increases with group size, but a substantial proportion of conditionally cooperative strategies prevail. At the aggregate level, we find that proportional tit-for-tat explains cooperation decisions well.

View Alex’s professional website.