knowledge, for instance, Player A knows before the game even starts that if he and B both choose to defect, they will each get I point In an iterated game, the two players play repeatedly; thus after finishing one game, A and B may play another(Admittedly, there is a little confusion in the terminology here; thus we refer to each iteration as a"play, which constitutes a single"round " of the larger iterated game. ) There are a number of ways in which iterated games may be played; in the simplest situation, A and B play for some fixed number of rounds(say 200), and before each round, they are able to look at the record of all previous rounds. For instance, before playing the tenth round of their iterated game, both a and b are able to study the sults of the previous nine rounds An Analysis of a simple game matrix The game depicted by the matrix above is a particularly easy one to analyze. Let's examine the situation from Player A's point of view(Player B's point of view is identical) Suppose B cooperates. Then I do better by cooperating myself (I receive five points instead of three). On the other hand, suppose b defects. I still do better by cooperating (since I get two points instead of one). So no matter what B does, I am better off cooperating Player B will, of course, reason the same way, and both will choose to cooperate In the terminology of game theory, both a and b have a dominant choice -i. e, a choice that gives a preferred outcome no matter what the other player chooses to do. The matrix shown above, by the way, does not represent a prisoner's dilemma situation, since when both players make their dominant choice, they also both achieve their highest personal scores. Well see an example of a prisoner's dilemma game very shortly To re-cap: in any particular game using the above matrix, we would expect both players to cooperate, and in an iterated game, we would expect both players to cooperate repeatedly, on every round The Prisoner's Dilemma game matrix Now consider the following game matrix B defects A cooperates gets 3 B gets 3 B gets 5 A defects a gets 5 B gets 0 B gets 1 what Plava farers A and b both have a dominant choice -namely, defection. No matter layer B does, Player A improves his own score by defecting, and vice versaknowledge; for instance, Player A knows before the game even starts that if he and B both choose to defect, they will each get 1 point. In an iterated game, the two players play repeatedly; thus after finishing one game, A and B may play another. (Admittedly, there is a little confusion in the terminology here; thus we refer to each iteration as a “play,” which constitutes a single “round” of the larger, iterated game.) There are a number of ways in which iterated games may be played; in the simplest situation, A and B play for some fixed number of rounds (say 200), and before each round, they are able to look at the record of all previous rounds. For instance, before playing the tenth round of their iterated game, both A and B are able to study the results of the previous nine rounds. An Analysis of a Simple Game Matrix The game depicted by the matrix above is a particularly easy one to analyze. Let's examine the situation from Player A's point of view (Player B's point of view is identical): “Suppose B cooperates. Then I do better by cooperating myself (I receive five points instead of three). On the other hand, suppose B defects. I still do better by cooperating (since I get two points instead of one). So no matter what B does, I am better off cooperating.” Player B will, of course, reason the same way, and both will choose to cooperate. In the terminology of game theory, both A and B have a dominant choice - i.e., a choice that gives a preferred outcome no matter what the other player chooses to do. The matrix shown above, by the way, does not represent a prisoner's dilemma situation, since when both players make their dominant choice, they also both achieve their highest personal scores. We'll see an example of a prisoner's dilemma game very shortly. To re-cap: in any particular game using the above matrix, we would expect both players to cooperate; and in an iterated game, we would expect both players to cooperate repeatedly, on every round. The Prisoner's Dilemma Game Matrix Now consider the following game matrix: B cooperates B defects A cooperates A gets 3 A gets 0 B gets 3 B gets 5 A defects A gets 5 A gets 1 B gets 0 B gets 1 In this case, Players A and B both have a dominant choice - namely, defection. No matter what Player B does, Player A improves his own score by defecting, and vice versa