Consider the following general Prisoner’s Dilemma
player 2
player 1 Deny Confess
Deny R;R S; T
Confess T; S 0; 0
Assume that 2R > S + T; and T > R > 0 > S:
a. Show that Grim/ Trigger strategy when played by both players is a sub-game perfect
equilibrium for infinitely repeated games.
b. Show that Tit-for-Tat is not sub-game perfect in the infinitely repeated Prisoner’s
Dilemma with no discounting.