If I defect but you cooperate, then I get to spend all day on the beach and still get a good grade—the best outcome for me, the worst for you.
! No, it’s not. The “you” in this example prefers getting a good grade and privately fuming about having to do the work themselves to failing and not having to do the work. (And actually, for many of the academic group projects I’ve been involved in, it’s less and happier work for the responsible member to do everything themselves, because there’s too little work for too many people otherwise.)
The basic solution to the prisoner’s dilemma: the only winning move is not to play. When you find a payoff matrix that looks like the prisoner’s dilemma when denominated in years, add other considerations to the game until it is no longer the prisoner’s dilemma when denominated in utility.
What’s neat about that statement of the solution is that it naturally extends in every direction. Precommitments are an attempt to add another consideration- and their credibility is how much utility it looks like you can bestow to them. “My utility for punishing my daughter’s defiler is higher than my utility for having clean carpets” is easy to believe, “my utility for keeping my commitments is higher than my utility for being $20,000 richer” is difficult to believe. (Scale should impact willingness to accept on an ultimatum game.)
The basic solution to the prisoner’s dilemma: the only winning move is not to play. When you find a payoff matrix that looks like the prisoner’s dilemma when denominated in years, add other considerations to the game until it is no longer the prisoner’s dilemma when denominated in utility.
I don’t understand this, please explain. Suggesting to “add other considerations to the game until it is no longer the prisoner’s dilemma when denominated in utility” seems about equivalent to lying to yourself about what you really want (what your utility is) in order to justify doing something.
So if you have a chance to explain what you mean I would appreciate it.
I don’t understand this, please explain. Suggesting to “add other considerations to the game until it is no longer the prisoner’s dilemma when denominated in utility” seems about equivalent to lying to yourself about what you really want (what your utility is) in order to justify doing something.
“Features” might be a clearer word than “considerations.” [edit] For example, consider the group project example. If you just look at the amount of work done, it’s a prisoner’s dilemma, with the result that no one does any work. When you look at the whole situation, you notice that, oh, grades are involved- and so it’s not a prisoner’s dilemma at all, because everyone (presumably) prefers passing the project and working to failing the project and not working. That’s a ‘consideration’ or ‘feature’ that gets added to the game to make it not a PD.
“Utility” is the numerical score you assign to the desirability of a particular future, and it has some neat properties when it comes to probabilistic reasoning. For example, if going to the beach has a utility of 5 and hitting yourself in the head with a hammer has a utility of −20, then a 80% chance of going to the beach and a 20% chance of hitting yourself in the head with a hammer has a utility of 0, and you should be indifferent between that gamble and some other action with a utility of 0. If you aren’t indifferent, then you mismeasured your utilities!
Game theory is the correct way to go from payoff matrices to courses of action, but the issue is that the payoff matrices are subjective. Consider one gamble, in which you and your partner both go free with 95% probability and both go to prison for 20 years with 5% probability. Would you be indifferent between that and it being certain that you would go to prison for 1 year and your partner would go to prison for 20 years? The Alice and Bob Yvain described would be. It’s what they really want. Is it any surprise that the right play for monsters like that is to defect?
For most humans, that’s not what they really want. They do actually care about the well-being of others; they care about having a good reputation and high standing in their community; they care about being proud of themselves and their actions. Their utility score is more than just 0 minus the number of years they spend in prison.
And so if Alice and Bob are in a situation where Alice prefers CC to DC, and Bob prefers CC to CD, then CC is now a Nash equilibrium- and both of them can securely take it. When people look at the Prisoner’s Dilemma and say “Defecting can’t be the right strategy,” they’re often doing that because they disbelieve the payoff matrix.
Because when you accept the payoff matrix, the answer is already determined and it’s just a bit of calculation to find it. Is 0 better than −15? Yes. Is −1 better than −20? Yes. If you agree with both of those statements, and expect your opponent to agree with both statements, then the story’s over, and both players defect.
! No, it’s not. The “you” in this example prefers getting a good grade and privately fuming about having to do the work themselves to failing and not having to do the work. (And actually, for many of the academic group projects I’ve been involved in, it’s less and happier work for the responsible member to do everything themselves, because there’s too little work for too many people otherwise.)
The basic solution to the prisoner’s dilemma: the only winning move is not to play. When you find a payoff matrix that looks like the prisoner’s dilemma when denominated in years, add other considerations to the game until it is no longer the prisoner’s dilemma when denominated in utility.
What’s neat about that statement of the solution is that it naturally extends in every direction. Precommitments are an attempt to add another consideration- and their credibility is how much utility it looks like you can bestow to them. “My utility for punishing my daughter’s defiler is higher than my utility for having clean carpets” is easy to believe, “my utility for keeping my commitments is higher than my utility for being $20,000 richer” is difficult to believe. (Scale should impact willingness to accept on an ultimatum game.)
I don’t understand this, please explain. Suggesting to “add other considerations to the game until it is no longer the prisoner’s dilemma when denominated in utility” seems about equivalent to lying to yourself about what you really want (what your utility is) in order to justify doing something.
So if you have a chance to explain what you mean I would appreciate it.
“Features” might be a clearer word than “considerations.” [edit] For example, consider the group project example. If you just look at the amount of work done, it’s a prisoner’s dilemma, with the result that no one does any work. When you look at the whole situation, you notice that, oh, grades are involved- and so it’s not a prisoner’s dilemma at all, because everyone (presumably) prefers passing the project and working to failing the project and not working. That’s a ‘consideration’ or ‘feature’ that gets added to the game to make it not a PD.
“Utility” is the numerical score you assign to the desirability of a particular future, and it has some neat properties when it comes to probabilistic reasoning. For example, if going to the beach has a utility of 5 and hitting yourself in the head with a hammer has a utility of −20, then a 80% chance of going to the beach and a 20% chance of hitting yourself in the head with a hammer has a utility of 0, and you should be indifferent between that gamble and some other action with a utility of 0. If you aren’t indifferent, then you mismeasured your utilities!
Game theory is the correct way to go from payoff matrices to courses of action, but the issue is that the payoff matrices are subjective. Consider one gamble, in which you and your partner both go free with 95% probability and both go to prison for 20 years with 5% probability. Would you be indifferent between that and it being certain that you would go to prison for 1 year and your partner would go to prison for 20 years? The Alice and Bob Yvain described would be. It’s what they really want. Is it any surprise that the right play for monsters like that is to defect?
For most humans, that’s not what they really want. They do actually care about the well-being of others; they care about having a good reputation and high standing in their community; they care about being proud of themselves and their actions. Their utility score is more than just 0 minus the number of years they spend in prison.
And so if Alice and Bob are in a situation where Alice prefers CC to DC, and Bob prefers CC to CD, then CC is now a Nash equilibrium- and both of them can securely take it. When people look at the Prisoner’s Dilemma and say “Defecting can’t be the right strategy,” they’re often doing that because they disbelieve the payoff matrix.
Because when you accept the payoff matrix, the answer is already determined and it’s just a bit of calculation to find it. Is 0 better than −15? Yes. Is −1 better than −20? Yes. If you agree with both of those statements, and expect your opponent to agree with both statements, then the story’s over, and both players defect.