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Why I give my students a ‘tragedy of the commons’ extra credit challenge

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Re: Why I give my students a ‘tragedy of the commons’ extra credit challenge

#81

Post by tolmasky »

s73v3r wrote: post #80
tolmasky wrote: post #66

Earlier quoted context omitted.

It doesn't matter because the requirement is NO ONE choose it. There is nothing to gain by selecting 6. The second you are writing 6 down on your paper, you better hope the 4 extra points are worth more to you than $x because you have absolutely invalidated the game, not "maybe" invalidated it. If x is big enough to trivialize 4 points, I am pretty sure no one would choose it (or at least fell well below 10%). For ex…

Have I? Assuming that it's a large enough class to where there are at least a handful of slots for 6s, and the one rich kid is offering the money so they get the 6, I might choose 6 as well, betting that few enough people will decide to risk it.

The whole point is that the rich kid is offering the reward solely if no other people choose the 6. NOT if its 10%. By choosing the 6, you necessarily lose the money. Thus, you would only do that if the 6 points are more important to you than the reward, since you will absolutely lose the rich kid's reward if you choose it.

Re: Why I give my students a ‘tragedy of the commons’ extra credit challenge

#82

Post by swang »

fcbrooklyn wrote: post #63
makr17 wrote: post #38

Earlier quoted context omitted.

> "points" have no intrinsic value except in comparison to your classmates this would be true if the course was graded on a curve, but the article makes clear that > the course grades are not curved.

Doesn't matter if there's a curve. Your grades are still only meaningful compared to your classmates. (ok, assuming you're not in danger of actually failing the class)

The only time you care about your classmate's grade is when it is being graded on a curve. I couldn't care less about other people's grades.

Re: Why I give my students a ‘tragedy of the commons’ extra credit challenge

#83

Post by mtVessel »

lifeformed wrote: post #54
fcbrooklyn wrote: post #33

Actually, I think in this case the only rational choice is to ask for the 6 points. One of two things will happen: 1) Less than 10% will follow suit, in which case you'll get a 6 point boost, and you'll have secured an advantage over 90% of your classmates. 2) More than 10% will follow suit, and noone will get anything, in which case you will have no advantage over your classmates, and neither will any classmate have…

I think it also depends on the class size. If there are only 10 students, then it's very risky to pick 6 points, since you have to be the only one who picks it. But if there are 1,000 students, then it'd make perfect sense to pick 6 points. Basically, the less of an effect your own decision has on the group outcome, the more rational it is to pick the selfish decision. This is why I find voting hard to justify if you…

If you live in the same country as I do, I definitely think you shouldn't vote. That way, my vote counts more.

Huh?

If everyone's vote carries the same weight, then in a large pool, everyone's vote is equally meaningless. So, logically, if my vote is almost certainly not going to cast the deciding ballot, then I should stay home. And so should everyone else.

If everyone stays home, then all it takes for my candidate to win is for me to go to the polls. All of a sudden, my vote is the most meaningful vote in the entire election!

"Everyone's vote counts equally" only applies to those who actually, y'know, vote.

Or, try this argument: The premise of voting is not that it matters whose vote tips the scales. The premise of voting is that the candidate who gets the most people to vote for him or her wins. So you only need to vote if you actually care who wins. And if you do care who wins, you don't actually care about the relative contribution of any individual vote, including your own.

Re: Why I give my students a ‘tragedy of the commons’ extra credit challenge

#84

Post by alelefant »

paulsutter wrote: post #32

The professor omitted the sole interesting number: what percentage of students choose 6 points. Is it typically 15% or is it typically 80%? It makes a huge difference. Most likely, it's a percentage low enough to indicate that the 10% threshold is carefully chosen. Otherwise he'd tell us. This is evidence that he has an agenda to promote (that people are too selfish), and that the facts don't support his agenda (most…

Your speculation != evidence

Re: Why I give my students a ‘tragedy of the commons’ extra credit challenge

#85

Post by deelowe »

fcbrooklyn wrote: post #63
makr17 wrote: post #38

Earlier quoted context omitted.

> "points" have no intrinsic value except in comparison to your classmates this would be true if the course was graded on a curve, but the article makes clear that > the course grades are not curved.

Doesn't matter if there's a curve. Your grades are still only meaningful compared to your classmates. (ok, assuming you're not in danger of actually failing the class)

The only time I cared about classmates' grades is when there was a curve. Adjusting a 92 to be the threshold for a 4.0 is a curve BTW. A lot of schools dont do this.

Re: Why I give my students a ‘tragedy of the commons’ extra credit challenge

#86

Post by deelowe »

justonepost wrote: post #5
andresmanz wrote: post #3

> I’ve been giving it to students since 2008, and only one class has successfully mastered the challenge. That's a real surprise. The 2 points option is the safe one, so everyone should go with that. Sure, I could assume that all (or most) of the other students think so and just get the 6 points myself. But then again, chances are that the other students think the same. So let's just go with the safer 2 points.

No, the safe option is to get organized and plan out who is going to chose the 6 points. That way, you know if you secretly chose the 6 points when you were supposed to get 2, you will get nothing. Then it doesn't become tragedy of commons, but rather an experiment with vandalism. The experiment, IMO, isn't valid. In RL tragedy of commons, the selfish don't really suffer that much .. it's usually everyone else that d…

Yep. A better example would be to make it so that 10% of the students get 6 extra points and the rest get none if more than 10% choose 6 extra points. This way everyone that chooses 2 is punished if the go over.

Re: Why I give my students a ‘tragedy of the commons’ extra credit challenge

#87

Post by lifeformed »

mtVessel wrote: post #83
lifeformed wrote: post #54

Earlier quoted context omitted.

I think it also depends on the class size. If there are only 10 students, then it's very risky to pick 6 points, since you have to be the only one who picks it. But if there are 1,000 students, then it'd make perfect sense to pick 6 points. Basically, the less of an effect your own decision has on the group outcome, the more rational it is to pick the selfish decision. This is why I find voting hard to justify if you…

If you live in the same country as I do, I definitely think you shouldn't vote. That way, my vote counts more. Huh? If everyone's vote carries the same weight, then in a large pool, everyone's vote is equally meaningless. So, logically, if my vote is almost certainly not going to cast the deciding ballot, then I should stay home. And so should everyone else. If everyone stays home, then all it takes for my candidate…

All of this is true; however, at the end of the day, it still seems bothersome that me voting and me not voting has the exact same outcome. It won't affect anything. Even if I care who wins.

Some people say, "well, if everyone who thought like you voted instead, they could make a difference." Okay, fine, you're right, I'll vote instead then. I do, and it's still logically equivalent to not voting.

I mean, obviously we should all vote, but it just always seemed weird to me that society relies on everyone performing an individually inconsequential action.

Re: Why I give my students a ‘tragedy of the commons’ extra credit challenge

#88

Post by Smushman »

Amorymeltzer wrote: post #16
Smushman wrote: post #11

I see it as a simple equation. I don't think it says more than that about people. Can someone enlighten me as to why a 90% break point? Why not for example 50%? Is it because 90% introduces some level of collaboration or vice versa? Sans collaboration or any other useful information (people I may already know in the class, etc.), I would say at best you have a 50/50 chance of a total stranger choosing the option that…

I imagine it's because 10% kicks in really easy and requires the you to stop and think about your actions. If you need a full 50%, screw it, go for 6, almost everyone else will. At 10%, though, you stand a fairly good chance of being the tipping point.

With the given caveat that any more than 10% of the group requesting 6 voids the whole thing, it seemed a foregone conclusion to expect 0 points. On the off chance I am wrong about that, I would end up with 6.

So the final conclusion I had == highly likely 0, but a very small chance of 6.

2 points were statistically ruled out the moment I heard 10%.

I see how the thinking re: screw it though also is valid. Thanks.

Re: Why I give my students a ‘tragedy of the commons’ extra credit challenge

#89

Post by s73v3r »

tolmasky wrote: post #81
s73v3r wrote: post #80

Earlier quoted context omitted.

Have I? Assuming that it's a large enough class to where there are at least a handful of slots for 6s, and the one rich kid is offering the money so they get the 6, I might choose 6 as well, betting that few enough people will decide to risk it.

The whole point is that the rich kid is offering the reward solely if no other people choose the 6. NOT if its 10%. By choosing the 6, you necessarily lose the money. Thus, you would only do that if the 6 points are more important to you than the reward, since you will absolutely lose the rich kid's reward if you choose it.

But all votes are anonymous, so the rich kid wouldn't know.

Re: Why I give my students a ‘tragedy of the commons’ extra credit challenge

#90

Post by mtVessel »

lifeformed wrote: post #87
mtVessel wrote: post #83

Earlier quoted context omitted.

If you live in the same country as I do, I definitely think you shouldn't vote. That way, my vote counts more. Huh? If everyone's vote carries the same weight, then in a large pool, everyone's vote is equally meaningless. So, logically, if my vote is almost certainly not going to cast the deciding ballot, then I should stay home. And so should everyone else. If everyone stays home, then all it takes for my candidate…

All of this is true; however, at the end of the day, it still seems bothersome that me voting and me not voting has the exact same outcome. It won't affect anything. Even if I care who wins. Some people say, "well, if everyone who thought like you voted instead, they could make a difference." Okay, fine, you're right, I'll vote instead then. I do, and it's still logically equivalent to not voting. I mean, obviously w…

That's because the worth of votes are in aggregate, not individually. Individually infinitesimal is not the same thing as individually inconsequential.

"No snowflake in an avalanche ever feels responsible." -Stanislaw Jerzy

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