The Prisoners Dilemma – book by William Poundstone – blog by Karl Janowski
“Cooperate or defect?” that is the question. In The Prisoners Dilemma, William Poundstone takes us though the game and history explaining the origins of game theory. History of Von Neumann and the atomic bomb are used to show instances of the prisoner’s dilemma, a zero sum game.
act to maximize the minimun that will be left for you (cake cutters example)
maximin - the maximum row minimum
In the prisoners dilemma there is every temptation to defect.
If the end is known, always tempting to cheat at the end.
| | | Player 2 | |
| | | Defect | Cooperate |
| Player 1 | Defect | DD | DC |
| Cooperate | CD | CC | |
There are twenty four (4*3*2*1) different combinations of payoffs.
Four that have temptation to defect (read DC as “you defect he cooperates”):
DC>DD>CC>CD - Deadlock – both prefer to defect both try to get the other to cooperate
DC>CC>DD>CD – Prisoners Dilemma – highest payoff is if you defect and the other coops
DC>CC>CD>DD – Chicken – two drive at each other – defect is stay the course, coop is flee
CC>DC>DD>CD – Stag Hunt – all hunt deer, or you defect and hunt rabbits but that hurts the groupVolunteer's dilemma is multiplayer chicken - lights go out who call the electric company?
Does an irrational player in chicken have an advantage?
Tit for Tat Strategy
Tit for tat - Cooperate on the first round and on the second mimic what they did on the first
Versions like 90% Tit for Tat – stops random pinging because you don’t always return a defect . An example is in the movie Godfather the Godfather “forgoes the vengeance of his son” to stop the violence
Tit for tat with random defection – can it sometimes beat tit for tat
Shubik’s Dollar Auction
Addiction in a game – has two rules
1.) A dollar goes up for auction for the highest bid. Each bid must be higher than the last one and the game ends when there are no more bids in a time period.
2.) The second highest bidder must pay the amount of his last bid and get nothing in return. You don’t want to be the second highest bidder.
Winner-take all auction