Correlation, Learning and the Robustness of Cooperation

In the stage game Prisoner's Dilemna one line of research which is pursued to justify the cooperative outcome is based upton some idea of correlation. This paper aims at testing whether correlation could support a cooperative behavior in the long run, by embedding the infinitely repeataed game within a simple evolutionary framework. In particular, the main theorem states that just two born cooperative agents might remain cooperative forever with strictly positive probability. This robustness result appears to be particularly strong since the model allows cooperative agents to switch strategy and start defecting from a certain time onward, but not vice versa. (Copyright: Elsevier)