Prisoner's Dilemma

The Prisoner's Dilemma is a particular problem (or game) in the field of Game Theory. The details of the game will be discussed in class. The information below pertains only to this web-based Tournament software.

You will be asked to create a strategy (actually, up to 3 different strategies, if you want) using a tiny computer language that we've created for the occasion, called PDS (Prisoner's Dilemma Strategy language).

For the PDS exercises and for the Tournament, the payoff matrix is:

		Player 2
		Cooperate	Defect
Player 1	Cooperate	3, 3	0, 5
Player 1	Defect	5, 0	1,1

This means that in any particular move, if, for instance, Player 1 cooperates, and Player 2 defects, then Player 1 will get 0 points, and Player 2 will be 5 points.

Terminology

Strategy: you will develop a strategy and then encode that strategy as a PDS program. The terms "Player" and "Strategy" mean the same thing here.

Move: a single action in a game. For instance, in one move, Player 1 defects and Player 2 cooperates.

Game: a sequence of moves between two particular players in the Iterated Prisoner's Dilemma. For instance, a game may consist of 15 moves, at the end if which each player is given a total game score (sum of the move scores).

Tournament: a set of games wherein every strategy is pitted once against every other strategy. That means that if there are 30 students, with each student submitting 3 strategies, there will be 90 different strategies competing against each other, and the tournament will consist of 90*89/2 = 4,005 games.