We investigate and compare different approaches to derive strategies from observed data in spatial and spaceless prisoners' dilemmas experiments. We start with a model where players choose a fixed action that remains constant for all repetitions of a stage game. As an extension we then allow...

We experimentally study the effects of locality in a repeated prisoners' dilemma. We compare players located on a circle with those in neighbourless groups. On circles players interact only with neighbours, but not with distant players. In groups all players interact with each other in the same...

In this paper we argue that authorities aid cooperation by means ofdirect coordination or the enforcement of re-commitment devices suchas contract laws.Credible threats of violence allow this role. In alocal interaction model, an authority forms if mutually connected individuals with sufficient...