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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)

#81

Post by 6502nerdface »

jzl wrote: post #55

I've seen a couple of oblique references to this in other comments, but I'll go a little deeper: if you want to truly understand the prisoner's dilemma scenario and how it relates to human, or more generally, animal behavior, there is incredible coverage of the topic in Richard Dawkins' The Selfish Gene. He pioneered the idea of running PD "competitions" in an attempt to discover the best evolutionary strategy for PD…

> 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

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

#82

Post by GuB-42 »

freech wrote: post #78

This does not at all explain human behaviour: Most people would not shovel all the snow themselves while their counterpart chills in their car. And many people cooperate in prisoner's dilemma situations. What explains human behaviour is that with every action we program ourselves to follow certain strategies and rules and that others can judge to some extent which strategies we programmed ourselves to follow. Thus we…

This is tit-for-tat.

Always start by cooperating and then do the same as the other party : cooperate if he does, retaliate if he doesn't. It is the most effective strategy in both games.

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

#83

Post by shkkmo »

dandare wrote: post #59

I always considered the pay-offs in PD to be variables with various positive or negative values. That would make SD is just a subset of PD with different pay-offs.

There is a difference in the relations between the two payoff schemes.

In PD, if you don't cooperate, I'm better off not cooperating

In SD, if you don't cooperate, I'm better off still cooperating

This means that don't cooperate / don't cooperate is not the nash equilibrium in SD like it is in PD.

In SD the nash equilibriums are one person shoveling.

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

#84

Post by freech »

GuB-42 wrote: post #82
freech wrote: post #78

This does not at all explain human behaviour: Most people would not shovel all the snow themselves while their counterpart chills in their car. And many people cooperate in prisoner's dilemma situations. What explains human behaviour is that with every action we program ourselves to follow certain strategies and rules and that others can judge to some extent which strategies we programmed ourselves to follow. Thus we…

This is tit-for-tat. Always start by cooperating and then do the same as the other party : cooperate if he does, retaliate if he doesn't. It is the most effective strategy in both games.

No it's not. What needs to be explained is why you cooperate if you know that you will never play with the same person again. And the answer is that by doing so you get in the habit of automatically cooperating in similar situations in the future and other people recognize this habit and trust you.

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

#85

Post by kobeya »

lisper wrote: post #61
quadrangle wrote: post #48

Earlier quoted context omitted.

You're correct in most of your description, but it's STILL a dilemma. It's a game of chicken. The dilemma is wanting to wait to see what the other player decides, so the dilemma is everyone refusing to decide. https://en.wikipedia.org/wiki/Snowdrift_game (redirects to chicken game)

You're right. In fact, upon reflection, it is the PD which is not really a dilemma but rather a paradox. The logically correct move in PD (assuming a purely utilitarian quality metric) is always clear: if the game is non-iterated (or iterated with a known horizon) then defect. Otherwise play tit-for-tat. This is true no matter what your opponent does. In the SD the logically correct move depends on your prior on what…

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

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

#87

Post by guiambros »

You can't talk about explaining Prisoner's Dilemma these days without mentioning Nicky Case's excellent "Evolution of Trust". My 5yo simply loves the game.

Btw, if you are into data viz or simply enjoy Bret Victor-inspired interactive programming, Nicky has tons of similar experiments worth checking out [2].

[1] http://ncase.me/trust/

[2] http://ncase.me/

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

#88

Post by jonahx »

theobon wrote: post #77
kbenson wrote: post #74

Earlier quoted context omitted.

> - The agent must have a good chance of competing against the opponent more than once. I was actually thinking about this the other day. I was wondering how much the population size and matching algorithm in the iterated Prisoner's Dilemma matter to the strategy outcome. I suspect it's quite a lot, given that if you never play the same opponent again, strategies that defect often should come out quite well, but if y…

http://ncase.me/trust/ is a great explainer that explores that question. How do different strategies compare depending on number of repeat interactions, population diversity and noise.

I really like this, but had to stop halfway through because my laptop overheated and went to sleep.

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

#89

Post by brownbat »

6502nerdface wrote: post #81
jzl wrote: post #55

I've seen a couple of oblique references to this in other comments, but I'll go a little deeper: if you want to truly understand the prisoner's dilemma scenario and how it relates to human, or more generally, animal behavior, there is incredible coverage of the topic in Richard Dawkins' The Selfish Gene. He pioneered the idea of running PD "competitions" in an attempt to discover the best evolutionary strategy for PD…

> 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.

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

#90

Post by vacri »

jerf wrote: post #33
rhizome wrote: post #30

Earlier quoted context omitted.

Is there an option to install a fisheye mirror so people in the driveway can see perpendicularly down the street? https://www.reflectionproducts.com/images/View-car-200-feet-...

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.
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