Strategies in the infinitely repeated Prisoner's dilemma:- Represent each of the following strategies s in an infinitely repeated Prisoner's Dilemma in a diagram like Figure.

a. Choose C in period 1, and after any history in which the other player chose C in every period except, possibly, the previous period; choose D after any other history. (That is, punishment is grim, but its initiation is delayed by one period.)

b. Choose C in period 1 and after any history in which the other player chose D in at most one period; choose D after any other history. (That is, punishment is grim, but a single lapse is forgiven.)

c. (Pavlov, or win-stay, lost-shift) Choose C in period 1 and after any history in which the outcome in the last period is either (C, C) or (D, D); choose D after any other history. (That is, choose the same action again if the outcome was relatively good for you, and switch actions if it was not.)