Published in Journal of Mathematical Sociology, 5 (1977), 173–186. |
This paper demonstrates the existence of a partial tit-for-tat (matching) strategy which, when used by one player in an iterated “Prisoner’s Dilemma” game, will induce a response of pure cooperation in the other player if that player behaves optimally. The minimum matching frequency of such a strategy is shown to be monotonically related to the Rapoport-Chammah “Cooperation Index”.