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Resilient cooperators stabilize long-run cooperation in Prisoner’s Dilemma

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Re: Resilient cooperators stabilize long-run cooperation in Prisoner’s Dilemma

#51

Post by Nomentatus »

mizzao wrote: post #43
visarga wrote: post #20

Earlier quoted context omitted.

Great post and wonderfully illustrated! The prisoner dilemma also ties into the tragedy of the commons: when multiple players decide to defect and exploit the commons to the fullest, then commons lose their value for all. It is also related to temporal discounting - we prefer to pollute today and ignore the price tag we will face in the future. We know so much about game theory yet we can't apply it in politics, beca…

The n-player PD is also known as the public goods game, and is used to study cooperation as well. Another meta-conclusion I would draw from our paper is that current game theory is insufficient to explain what we observe in real life, including politics, negotiation, and so on. It is folly to apply hyperrationality (strict economic modeling) to real human behavior, and part of the goal of our work is to stimulate mor…

The PD is important because it's mostly the rational selfish actors who we need to worry about. Irrationally altruistic actors are rare, and irrational selfish actors tend to self-immolate or get arrested quickly. Many things go on during church socials that don't require any problem-solving on the part of game theorists; because widespread altruism is already a solution, just the hardest solution to actually get to.

Re: Resilient cooperators stabilize long-run cooperation in Prisoner’s Dilemma

#52

Post by Nomentatus »

saycheese wrote: post #18
sinan_si wrote: post #16

Similar research to whom anyone interested in these topics : https://www.researchgate.net/publication/303656078_The_Dose_...

Resilent cooperation is intentional, but cooperating based on a lack of memory is not - guess the question is if it matters if the source of constant behavior matters, and if so, why?

I certainly presume that it matters because the other player must have a theory of mind, and see a string of non-cooperative plays as an intentional penalty, and therefore predictive; that is something said other player can control by behaving better themselves in future.

Re: Resilient cooperators stabilize long-run cooperation in Prisoner’s Dilemma

#53

Post by Nomentatus »

mizzao wrote: post #38
saycheese wrote: post #25

Earlier quoted context omitted.

Realize that saying something is "obvious" is often not the case, though by definition resilience adds stability and in a dynamic system any addition of any truly resilient element is amplifier of stability, especially in a finite system. If you're saying that the resilient players might switch to being non-resilient, sure, it's not obvious what would happen, but my assumption is that a resilient player is resilient.

It was not obvious that resilient cooperative players even existed before we conducted this experiment. Now it's obvious, because we run into nice, prosocial people and of course they fit the profile.

It's not obvious until you prove it, I'll buy that since I wasn't able to win this argument, a few decades ago. I remember being in Philosophy class trying to argue (decades ago now) that tit-for-tat tests were too narrow (too short) and that lagged-strategies (as I then called them) should work better than tit-for-tat in longer trials. The problem I saw with tit-for-tat being that you can get mutually locked into it; it's very common in real life to have two players/friends/spouses thinking the other began a barrage of mutual retaliation first. So incorporating at least brief resets or periods of forgiveness seemed a better strategy to me. An example of this lock-in from real life is that people who (often do to an abusive childhood) commonly misread others actions as deliberately hurtful to them end up divorced, or not able to get to marriage in the first place, often after a ton of tit-for-tat fights they think their partner started. Ditto, those who don't spend a lot of time thinking about the consequences for others of their actions or whether those could be misinterpreted.

Anyway, I made no headway with my professors (or other students, probably.) They were happy to call the results they then had proof that tit-for-tat was tops, and always would be 'cause it was such a simple, logical strategy. So, no, I can personally assure anyone who cares to know that it wasn't obvious to the experts then. As for laypeople... well it's most accurate to say they had no opinion; it was rough trying to explain PDs back then since they violated everyone's "folk expectations" in some way, whether you were religious or a rationalist and were rarely spoken or written of outside of academia.

I'd also say I didn't know it then, either; I just suspected - since it wasn't perfectly clear that my analogy from more ambiguous real-life exchanges would hold in such clearly-defined circumstances.

Re: Resilient cooperators stabilize long-run cooperation in Prisoner’s Dilemma

#54

Post by quadrangle »

mizzao wrote: post #21

Lead author of the paper here; AMA. The main novelty about this work is that we had 100 people play repeated PD for a month instead of The findings can be summarized in a sentence as "a minority of nice people can make everyone better off."

Is this like saying something like "if enough people self-sacrifice by donating to support public goods, it can be stable enough and we all get public goods, even if others freeride"? In other words, a critical mass of cooperators can keep going and support one another even if they are suffering from the effect of defectors who all still have incentive to keep defecting. Right?

Re: Resilient cooperators stabilize long-run cooperation in Prisoner’s Dilemma

#55

Post by quadrangle »

Ninjalicious wrote: post #4

I didn't read the article but the headline makes me postulate that this is because the optimal individual strategy in Prisoner's Dilemma is tit-for-tat. Respond in kind to every action taken against you. If someone offends, attack, if they offer peace, be peaceful. Nice people will more often offer the olive branch (sub-optimally), so anyone else playing the optimal strategy will offer it back. Over time this probabl…

I only skimmed the article, but I'm pretty sure that tit-for-tat as a strategy is not the relevant point. The point is that there are people whose strategy is always-cooperate, and enough of those players in a group results in a situation that will stabilize to having a decent amount of real cooperation. Tit-for-tat might have some similar results but probably would need a greater number of tit-for-tat players for stability versus the critical mass of always-cooperate players needed for stability (my speculation).

Re: Resilient cooperators stabilize long-run cooperation in Prisoner’s Dilemma

#56

Post by uhisatum »

mizzao wrote: post #21

Lead author of the paper here; AMA. The main novelty about this work is that we had 100 people play repeated PD for a month instead of The findings can be summarized in a sentence as "a minority of nice people can make everyone better off."

Thanks for taking time to answer questions! I have two short questions.

1. Are there any plans to make the dataset available?

2. I missed this, what incentive is there for players to "unravel", or move the first round of defection earlier? My naive thought is that turkers want to maximize monetary payoff by getting a high bonus (1 cent for each 2 points earned) and playing quickly (to free up time for other HITs). From your payoff matrix, both players cooperating all ten rounds in one game each get 50 points. A player could instead defect on round 10 to get 52 points. He could also defect on round 9 and expect mutual defection on round 10 to get 50 points. But if he defects even earlier on round 8 and expects mutual defection afterwards, he gets 48 points. In this experiment, earlier and earlier defections seem worse than cooperating on all rounds, even for the defector.

Re: Resilient cooperators stabilize long-run cooperation in Prisoner’s Dilemma

#57

Post by mizzao »

uhisatum wrote: post #56
mizzao wrote: post #21

Lead author of the paper here; AMA. The main novelty about this work is that we had 100 people play repeated PD for a month instead of The findings can be summarized in a sentence as "a minority of nice people can make everyone better off."

Thanks for taking time to answer questions! I have two short questions. 1. Are there any plans to make the dataset available? 2. I missed this, what incentive is there for players to "unravel", or move the first round of defection earlier? My naive thought is that turkers want to maximize monetary payoff by getting a high bonus (1 cent for each 2 points earned) and playing quickly (to free up time for other HITs). Fr…

Data is already available at https://osf.io/64z8u/. Full qualitative survey data will be available soon; but for now take a look at the supplementary materials.

If your opponent is going to defect at some point anyway, then if you defect right before he does you will be better off (at least for that game). That's the pressure to unravel.

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