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Game Theory Calls Cooperation Into Question

quantamagazine.org

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Re: Game Theory Calls Cooperation Into Question

#11
post #10
post #3

> In a single instance of the prisoner’s dilemma, the best strategy is to defect — squeal on your partner and you’ll get less time. No, that is not right, if it was there would be no dilemma, and this subject would not be discussed ad nauseam. The whole point is that the situation is symmetrical for both players, they should reach the same conclusion and act the same way ... and using the strategy of cooperation thei…

Cooperating is strongly dominated by defecting in Prisoners Dilemma. This is an obvious and very basic game theory result. Game Theory models strategic situations and doesn't offer insight outside what is modeled. If you think there should be communication supporting cooperation in the game, that game is NOT the Prisoners Dilemma and is in fact another game. The Prisoners Dilemma is a model that is stacked very much…

Iterated Prisoners dilemma is less clearly stacked in favour of defecting, although I assume that the actors' memories would fall under "communication":

http://en.wikipedia.org/wiki/Prisoner%27s_dilemma#The_iterat...

Re: Game Theory Calls Cooperation Into Question

#12
Pack animals like dogs naturally discourage fighting amongst themselves [1]. Strife weakens the pack.

Consider the effort it takes 1 person to build a house, or the amount of effort it would take to build an mp3 player alone from scratch.

Game theory would have you believe the optimal way to win at poker is to booby trap the card table and rob your competition.

[1] https://www.youtube.com/watch?v=hstLdzCg6l8

Re: Game Theory Calls Cooperation Into Question

#13

Perhaps "cooperation brings game theory into question" would be a better title?

You can't upvote this enough. If the predictions of your model don't square up with reality, reality that came into being through evolution on the geological timescale, it's time that you should look at the shortcomings of your model. Perhaps it can evolve into something with actual predictive value.

Re: Game Theory Calls Cooperation Into Question

#14
post #10
post #3

> In a single instance of the prisoner’s dilemma, the best strategy is to defect — squeal on your partner and you’ll get less time. No, that is not right, if it was there would be no dilemma, and this subject would not be discussed ad nauseam. The whole point is that the situation is symmetrical for both players, they should reach the same conclusion and act the same way ... and using the strategy of cooperation thei…

Cooperating is strongly dominated by defecting in Prisoners Dilemma. This is an obvious and very basic game theory result. Game Theory models strategic situations and doesn't offer insight outside what is modeled. If you think there should be communication supporting cooperation in the game, that game is NOT the Prisoners Dilemma and is in fact another game. The Prisoners Dilemma is a model that is stacked very much…

Thought experiments are not set in stone, and even if they were modifications could me made.

A real game show [1] put two people in a position of the prisoners dilemma and they were free to communicate. [2]

[1] https://www.youtube.com/watch?v=S0qjK3TWZE8

[2] http://www.radiolab.org/story/golden-rule/

Re: Game Theory Calls Cooperation Into Question

#15

Pack animals like dogs naturally discourage fighting amongst themselves [1]. Strife weakens the pack. Consider the effort it takes 1 person to build a house, or the amount of effort it would take to build an mp3 player alone from scratch. Game theory would have you believe the optimal way to win at poker is to booby trap the card table and rob your competition. [1] https://www.youtube.com/watch?v=hstLdzCg6l8

There's a theory that suggests altruism ultimately trumps selfishness within species, as aggressive warlike creatures would kill each other off ad-infinitum, where as cooperation ultimately strengthens individuals beyond the sum of their parts. [1]

[1] http://www.radiolab.org/story/103951-the-good-show/

Re: Game Theory Calls Cooperation Into Question

#16

Rather amusing title since it could be reworded as "Game theory still fails to explain biology." We know organisms cooperate. The fact that we consistently fail to find reasons to cooperate in game theory suggests that the simplifying assumptions that it makes are incorrect. To give only one example, what happens when agents can choose from among a set of games to play with opponents with known histories?

People do cooperate on a self-survival instinct though, cooperating now let's you get ahead of others together. However, there are always competition and hierarchies within the team/group as well that determine choices and game theory within the group cooperating. The larger the team or less dependent then the more each player may be unhappy or not doing the best for themselves personally.

For the most part, people cooperate when the outcome of cooperating puts them at a better place. In the same way everyone is unique but they copy proven paths to achieve certain ends or move to certain stages where they can eventually break off and get ahead personally. In the same way groups suck but we all live better that there are other people.

All of life is similar, self-interested for survival, but they want a place of their own and territory, eventually.

Re: Game Theory Calls Cooperation Into Question

#17
post #10
post #3

> In a single instance of the prisoner’s dilemma, the best strategy is to defect — squeal on your partner and you’ll get less time. No, that is not right, if it was there would be no dilemma, and this subject would not be discussed ad nauseam. The whole point is that the situation is symmetrical for both players, they should reach the same conclusion and act the same way ... and using the strategy of cooperation thei…

Cooperating is strongly dominated by defecting in Prisoners Dilemma. This is an obvious and very basic game theory result. Game Theory models strategic situations and doesn't offer insight outside what is modeled. If you think there should be communication supporting cooperation in the game, that game is NOT the Prisoners Dilemma and is in fact another game. The Prisoners Dilemma is a model that is stacked very much…

"domination" is a local phenomenon PD shows that local phenomena do not generalize to global solutions.

http://en.m.wikipedia.org/wiki/Superrationality

Re: Game Theory Calls Cooperation Into Question

#18

Rather amusing title since it could be reworded as "Game theory still fails to explain biology." We know organisms cooperate. The fact that we consistently fail to find reasons to cooperate in game theory suggests that the simplifying assumptions that it makes are incorrect. To give only one example, what happens when agents can choose from among a set of games to play with opponents with known histories?

One thing the article fails to discuss is Evolutionarily Stable Strategies. Dawkins discusses the idea in The Selfish Gene and The Extended Phenotype, and it can show how specific behaviors become resistant to invasion and thus settle in an equilibrium. It provides a much better model than the simple games.

Re: Game Theory Calls Cooperation Into Question

#19
>Researchers have proposed different possible mechanisms to explain cooperation. Kin selection suggests that helping family members ultimately helps the individual.

This is wrong and should significantly reduce any trust you may have had in the journalist who wrote the piece. Kin selection is about how helping family members helps the genes that make the individual. Behaviour will spread if it increases inclusive fitness. If you can save a sibling (coefficient of relatedness 0.5) with probability 1 and the chance of you dying is 0.4 you do it. If P(death) is 0.51 or higher you don't.

>Group selection proposes that cooperative groups may be more likely to survive than uncooperative ones.

The conditions necessary for group selection are incredibly strong and very rarely occur in practice in biological settings. When they do you get hive organisms like naked mole rats or the Hymenoptera. There is stronger evidence for group selection in cultural evolution than in most of biology.

Further reading http://lesswrong.com/lw/kw/the_tragedy_of_group_selectionism

>“As mutations that increase the temptation to defect sweep through the group, the population reaches a tipping point,” Plotkin said. “The temptation to defect is overwhelming, and defection rules the day.”

>Plotkin said the outcome was unexpected. “It’s surprising because it’s within the same framework — game theory — that people have used to explain cooperation,” he said. “I thought that even if you allowed the game to evolve, cooperation would still prevail.”

>The takeaway is that small tweaks to the conditions can have a major effect on whether cooperation or extortion triumphs. “It’s quite neat to see that this leads to qualitatively different outcomes,” said Jeff Gore, a biophysicist at the Massachusetts Institute of Technology who wasn’t involved in the study. “Depending on the constraints, you can evolve qualitatively different kinds of games.”

Mathematicians develop model that gives us a deeper understanding of the shallowness of our understanding of cooperation.

Unfortunately my math isn't strong enough to understand the paper but you'll get a much better understanding of how game theory applies to biology from The Selfish Gene by Richard Dawkins than from this article.

Don't read anything by Stephen Jay Gould http://pleiotropy.fieldofscience.com/2009/02/krugman-on-step...

http://en.wikipedia.org/wiki/Stephen_Jay_Gould#The_Mismeasur... In 2011, a study conducted by six anthropologists reanalyzed Gould's claim that Samuel Morton unconsciously manipulated his skull measurements,[82] and concluded that Gould's analysis was poorly supported and incorrect. They praised Gould for his "staunch opposition to racism" but concluded, "we find that Morton's initial reputation as the objectivist of his era was well-deserved."[83] Ralph Holloway, one of the co-authors of the study, commented, "I just didn't trust Gould. ... I had the feeling that his ideological stance was supreme. When the 1996 version of 'The Mismeasure of Man' came and he never even bothered to mention Michael's study, I just felt he was a charlatan."[84] The group's paper was reviewed in the journal Nature, which recommended a degree of caution, stating "the critique leaves the majority of Gould's work unscathed," and notes that "because they couldn't measure all the skulls, they do not know whether the average cranial capacities that Morton reported represent his sample accurately."[85] The journal stated that Gould's opposition to racism may have biased his interpretation of Morton's data, but also noted that "Lewis and his colleagues have their own motivations. Several in the group have an association with the University of Pennsylvania, and have an interest in seeing the valuable but understudied skull collection freed from the stigma of bias."

Re: Game Theory Calls Cooperation Into Question

#20
post #11
post #10

Earlier quoted context omitted.

Cooperating is strongly dominated by defecting in Prisoners Dilemma. This is an obvious and very basic game theory result. Game Theory models strategic situations and doesn't offer insight outside what is modeled. If you think there should be communication supporting cooperation in the game, that game is NOT the Prisoners Dilemma and is in fact another game. The Prisoners Dilemma is a model that is stacked very much…

Iterated Prisoners dilemma is less clearly stacked in favour of defecting, although I assume that the actors' memories would fall under "communication": http://en.wikipedia.org/wiki/Prisoner%27s_dilemma#The_iterat...

Yes, a repeated game like Iterated PD is a different game with a different solution. The Grim strategy for example.
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