Prisoner’s dilemma game

The evolution of cooperation is frequently analysed in terms of the repeated Prisoner s Dilemma game. Computer simulations show that the emergence of cooperation is a robust phenomenon. However, the strategy which eventually gets adopted in the population seems to depend sensitively on fine details of the modelling process, so that it becomes difficult to predict the evolutionary outcome in real populations. 

One can, of course, adopt the evolutionary viewpoint again. It reduces to drowning by numbers have lots of players play lots of Prisoner s Dilemma games for lots and lots of gen-... 

Thus we ought also to study the iterated Prisoner s Dilemma when the players have to take turns. The slight modification in such an alternating Prisoner s Dilemma game can affect the interaction to a considerable extent. For instance, if two Tit For Tat players engage in a Prisoner s Dilemma of the usual simultaneous kind, and if one of them defects by mistake, both players will subsequently cooperate and defect in turns. On the other hand, if two Tit For Tat players engage in an alternating Prisoner s Dilemma, and a unilateral defection occurs inadvertently, then the outcome will be an unbroken sequence of mutual defections. 

Boyd, R. (1989), Mistakes Allow Evolutionary Stability in the Repeated Prisoner s Dilemma Game, Journal of Theoretical Biology 136, 47—56. 

The players are A and B they can either cooperate C or defect D. In each cell are the payoffs to the two players based on the corresponding pair of choices the first payoff is A s, the second is B s. To make matters simple, we can assume perfectly symmetrical payoffs A and B could trade places in this matrix and nothing would change. (We will not maintain this assumption later in the analysis.) The classic Prisoner s Dilemma game is characterized by these conditions... 

In the best known of all games, the Prisoner s Dilemma, both players have a dominant strategy, that is, a strategy that is the best reply to all moves by the opponent ... 

This is an assurance game. There is no reason for anyone to cheat, but players must still be reassured that cooperation will be mutual, so as to avoid the cost of unilateralism. (2) The Prisoner s Dilemma could be modified by reversing the consequence of unilateral cooperation... 

The problem is made more interesting by playing it repeatedly with the same group of players, thereby permitting partial time histories of behaviour to guide future decisions. This so-called iterated prisoner s dilemma has drawn interest from game theorists for a while. 

Poundstone, W. Prisoner s Dilemma John von Neumann, Game Theory and the Puzzle of the Bomb. Doubleday Publishing (1993)... 

The most instructive and widely exercised computer model (by mathematicians, social scientists or biologists) is a simple game called Prisoner s Dilemma [332]. The idea of this approach is to simulate the... 

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