Repeated prisoner's dilemma
Instructions
You and a randomly chosen
co-player for several rounds of the prisoner?s dilemma game. After each
round a dice is thrown: if it shows 6, the game is stopped. Otherwise,
you will play another round with the same co-player.
In every round, each can
opt either for cooperation or defection. If both choose to cooperate, both
get 3 points each. If you both choose to defect, you get 1 point each.
If you choose defect and the other cooperate, you receive 5 points and
your co-player nothing. Conversely, if you cooperate and the other defects,
you receive nothing and the co-player gets 5 points.
Evaluations
Number of players: 22 (11 games)
Time evolution of mean payoff and frequencies
of R, S, T and P:
Notes
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Three games with persistent mutual cooperation.
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Two games where a unilateral defect occurred in the last round.
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The overall frequency of cooperate and defect is 75% to 25%.
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The repetitions increase cooperation from 50% to 75%.
Comments
Most players learn during the game to defect.
Thereby their payoff decreases.
If the game extends further, many learn to cooperate, however.
Written by Christoph Hauert