Play Contexts and Generic Prisoner’s Dilemma¶
There are four possible round outcomes:
- Mutual cooperation: \((C, C)\)
- Defection: \((C, D)\) or \((D, C)\)
- Mutual defection: \((D, D)\)
Each of these corresponds to one particular set of payoffs in the following generic Prisoner’s dilemma:
| Cooperate | Defect | |
|---|---|---|
| Cooperate | (R,R) | (S,T) |
| Defect | (T,S) | (P,P) |
For the above to constitute a Prisoner’s dilemma, the following must hold: \(T>R>P>S\).
These payoffs are commonly referred to as:
- \(R\): the Reward payoff (default value in the library: 3)
- \(P\): the Punishment payoff (default value in the library: 1)
- \(S\): the Sucker payoff (default value in the library: 0)
- \(T\): the Temptation payoff (default value in the library: 5)
A particular Prisoner’s Dilemma is often described by the 4-tuple: \((R, P, S, T)\):
>>> import axelrod
>>> axelrod.game.DefaultGame.RPST()
(3, 1, 0, 5)