Chapter 7. Prisoners Dilemma

Chapter 7. Prisoners’ Dilemma

12.	Identify which of the games in Figures 62–65 are prisoners’ dilemma games. Figure 62 Figure 63 Figure 64 Figure 65
13.	Both prisoners’ dilemma games in Figures 66 and 67 are played repeatedly with no definite last period. In which game are the players more likely to betray each other? Figure 66 Figure 67
14.	Both prisoners’ dilemma games in Figures 68 and 69 are played repeatedly with no definite last period. In which game are the players more likely to betray each other? Figure 68 Figure 69

Answers

12.	The games in Figures 63 and 64 are prisoners’ dilemmas. To be a prisoners’ dilemma game, a dominant strategy for both players is to be mean, and both players must be better off at the nice, nice outcome than the mean, mean one. Figure 62 is not a prisoners’ dilemma game because Player One has a dominant strategy of being nice. Figure 65 is not a prisoners’ dilemma game because Player Two is better off at the mean, mean outcome than the nice, nice outcome.
13.	If your opponent is being nice, you get an extra 2 from being mean in Figure 66 and an extra 15 from being mean in Figure 67. Consequently, betrayal is more profitable (and thus more likely) in Figure 67.
14.	Once you betray your opponent, you are likely to end up at the mean, mean outcome. The worse this outcome is, the less benefit there is to treachery. Consequently, betrayal is more costly (and thus less likely) in Figure 69.