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'Snowdrift' game tops 'Prisoner's Dilemma' in explaining cooperation (2007)

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Re: 'Snowdrift' game tops 'Prisoner's Dilemma' in explaining cooperation (2007)

#101

Post by briancleland »

brownbat wrote: post #89
6502nerdface wrote: post #81

Earlier quoted context omitted.

> If provoked, the agent will retaliate. > The agent is quick to forgive. Reminds me a bit of Marcus Aurelius: "From Rusticus... I learned... with respect to those who have offended me by words, or done me wrong, to be easily disposed to be pacified and reconciled, as soon as they have shown a readiness to be reconciled." http://directingmind.com/meditations#1-7

Such a progressive lesson to get from a guy who, in less tender moments, beheaded people who wouldn't make sacrifices to the gods. Humanity is weird.

Source?

Re: 'Snowdrift' game tops 'Prisoner's Dilemma' in explaining cooperation (2007)

#102

Post by majewsky »

Danihan wrote: post #76
majewsky wrote: post #65

Earlier quoted context omitted.

> Define righteous? Define immoral? The point here was that credit scores do not only rate your own behavior, but also those of people around you. If your neighborhood is bad, your credit score might reflect that instead of your own performance as a debtor. And if your neighborhood becomes hip and gains a better reputation, your credit score might improve even though you're still the same person.

Could you send me something reflecting why you think credit scores are based on the neighborhood in which you reside?

I live in Germany, where the zip code is a strong factor into the credit score. Source e.g. https://www.welt.de/finanzen/verbraucher/article13255357/Wer...

Re: 'Snowdrift' game tops 'Prisoner's Dilemma' in explaining cooperation (2007)

#103

Post by rwnspace »

vacri wrote: post #90
jerf wrote: post #33

Earlier quoted context omitted.

First, the point of these discussions is explicitly to stay within the lines. We all know there's a billion elaborations that you could make, but those are different problems. Worthy and interesting problems, even, but different problems. Second, there isn't always a great option for that, no.

'Staying within the lines' is why game theory doesn't actually work as a good predictor of human behaviour.

Not when applied without wisdom, but it's an excellent predictor of subsets of human behaviour, and a subset of those generalise well enough to satisfactorily explain existing phenomena. Simply because one has to be selective doesn't make it unworkable. It does make for misleading headlines, though.

Re: 'Snowdrift' game tops 'Prisoner's Dilemma' in explaining cooperation (2007)

#104

Post by avenius »

PeachPlum wrote: post #44

See also https://www.sciencedaily.com/releases/2016/09/160915085719.h... Two people can hunt deer together, but if they are alone, they can only hunt rabbits. The person belonging to the Envious group will choose to hunt rabbits because he or she will be at least equal to the other hunter, or maybe even better; the Optimist will choose to hunt deer because that is the best option for both hunters; the Pessimist will…

The fifth group must be the nihilists ;)

Re: 'Snowdrift' game tops 'Prisoner's Dilemma' in explaining cooperation (2007)

#105

Post by brownbat »

briancleland wrote: post #101
brownbat wrote: post #89

Earlier quoted context omitted.

Such a progressive lesson to get from a guy who, in less tender moments, beheaded people who wouldn't make sacrifices to the gods. Humanity is weird.

Source?

Np, check out accounts of the trial of Justin Martyr.

Re: 'Snowdrift' game tops 'Prisoner's Dilemma' in explaining cooperation (2007)

#107

Post by iainmerrick »

jzl wrote: post #100
iainmerrick wrote: post #71

Earlier quoted context omitted.

Richard Dawkins didn't pioneer that idea, it was Robert Axelrod. The seminal book about the topic is Axelrod's "The Evolution of Cooperation": https://en.wikipedia.org/wiki/The_Evolution_of_Cooperation (Dawkins was a prominent advocate of Axelrod's work, though. And "The Selfish Gene" is definitely a great read in its own right.)

Thank you for the correction. I read the book about 10 years ago and completely forgot that he wasn't talking about himself. Finally had a chance to look at the chapter again now and indeed he is discussing Axelrod's competitions in great depth.

If you haven't read Axelrod's book, give it a try -- it's absolutely terrific.

Re: 'Snowdrift' game tops 'Prisoner's Dilemma' in explaining cooperation (2007)

#108

Post by drvinceknight »

The Axelrod library is a Python implementation of the Prisoner's dilemma (tournaments, evolutionary dynamics etc) with over 200 strategies. It can also be used to study other games (http://axelrod.readthedocs.io/en/stable/tutorials/advanced/g...) so it would be straightforward to study the snowdrift game using it :)

Re some of the other comments about Robert Axelrod's tournament and evolution:

- As part of the project, the Axelrod library developers have written Python wrappers for the original Fortran code (https://github.com/Axelrod-Python/axelrod-fortran)

- Have used reinforcement learning to train strategies based on machine learning paradigms (https://arxiv.org/abs/1707.06307). EDIT: here are a couple of blog posts about recent research work http://vknight.org/unpeudemath/math/2017/07/28/sophisticated... and http://marcharper.codes/2017-07-31/axelrod.html

Disclaimer: I'm one of the maintainers of the project.

Re: 'Snowdrift' game tops 'Prisoner's Dilemma' in explaining cooperation (2007)

#109

Post by chriswarbo »

Smaug123 wrote: post #94
kobeya wrote: post #85

Earlier quoted context omitted.

That resolution only holds if you assume the other player to be equally rational in the PD.

In fact the strategy is simpler if the other player is exactly as rational as you: simply cooperate. The other player, being exactly as rational as you, will follow the same reasoning as you do to come to the same conclusion, and will do exactly the same thing as you. I would always cooperate with a copy of myself, for instance. https://en.wikipedia.org/wiki/Superrationality (Of course, the assumption "my opponent is…

There are variants of the prisoner's dilemma where you can check the 'rationality' of your opponent: the prisoners' decisions are chosen by computer programs, and each program is given the other program's source code as an argument. This is often referred to as "program equilibrium", and an optimal strategy is to cooperate iff running the other program with our own source code as an argument results in cooperation.

This runs into problems of computability though: if we run the opponent's code to see what it does, and it turns out that their program runs our code to see what we do, we can get stuck in an infinite loop.

Like most incomputable problems, we can take a conservative approach: try to prove that it cooperates, using some incomplete computable algorithm; defect if we can't prove it. One simple algorithm is to check if the source code is the same as ours; more sophisticated algorithms would perform static analysis of the code.

Re: 'Snowdrift' game tops 'Prisoner's Dilemma' in explaining cooperation (2007)

#110

Post by literallycancer »

brownbat wrote: post #105
briancleland wrote: post #101

Earlier quoted context omitted.

Source?

Np, check out accounts of the trial of Justin Martyr.

Skimming through the wikipedia page, it doesn't seem MA was personally involved in his death.

e: Never mind, I misread the original post.

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