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New Website Offers Provably Fair Solutions To Everyday Problems
An anonymous reader writes Carnegie Mellon researchers have just launched Spliddit, a website that offers methods for helping people split rent, divide goods, and share credit. The novelty is that these methods are all "provably fair": there are mathematical proofs showing that each algorithm on the site provides rigorous fairness guarantees. For example, the method for splitting rent is guaranteed to be envy free: the assignment of rooms and division of rent is such that a housemate would never want to swap places with another housemate. All it takes is a pair of siblings to prove that there's no such thing as "provably fair," non-mathematically.
I keep telling my dogs that the way that Spliddit divvies up the expenses is PROVABLY FAIR, but all they do is look at me blankly, cocking their heads to one side. Damn dogs. I never see a dime out of either of them.
Proverbs 21:19
Greece used something similar when trying to get people to honestly report the value of their antiquities. If they listed it for a price the government thought was too low, the agency could buy it for that price. I wish local governments would do something like that with home values. If they want to tax me for a house worth more than what I can get for it on the open market, then I should have the right to sell it to them at that price.
To divide ice cream equally between two kids, have one dish it out and the other choose. My parents did this with my brother and me, and there was never anything to fight about afterwards. You'll never see more precise measurement in your life, though.
Can we finally solve the age old question as to whether the seat should be left up or down? This is a function based on how many males vs females there are, and how often a male needs to, er, sit.
The male wants to avoid unnecessary raising and lowering - conservation of energy.
The female wants TWO things - she wants the seat lifted before the gentleman urinates, AND she wants it lowered before she does.
If the gentleman leaves the seat up, the female (provably) got the first thing she wants - the seat was raised before he urinated. Each party ends up doing the same amount of effort - they either raise or lower the seat before using it. That's fair.
The other option, that the seat is left down, means that a) the man is expected to do 100% of the work, both raising and lowering, while the female does none. More importantly from her point of view, if the seat is down, she doesn't know whether or not it was down when he peed. She might be sitting on pee spots.
Fairness, and her own piece of mind, therefore dictate that he leave the seat up.
However, if she's clever, she can't gently force the seat to be lowered afterwards by placing a tray of soaps, potpourri, etc. on top of the toilet. The tray will prevent the seat from being raised all way to vertical and gravity will ensure it ends up down. The clever gentleman can respond to this forcing function by pointing out that it prevents her from knowing whether male guests ever raised the seat at all.
Divorce is the prime example - it's rarely about the 2nd home, the dog, the china, etc.
It's about the cheating, the 'stealing the best years of my life', the drug addiction, etc.
Nine times out of ten, people are not really looking for 'fair', they want 'JUSTICE' (in quotes).
A pity, because in reality, 'JUSTICE" is another word for spending all your time and money on lawyers to punish someone else.
If their algorithms won't let you spend all your time and money on punishing your opponent, it won't actually solve all the problems of sub-dividing property.
excitingthingstodo.blogspot.com
Of course, for the splitting rent, the most fair approach is for the wealthiest roommate to pay more.
This is why I always pee in the shower. Problem solved!
Humans are slow, innaccurate, and brilliant; computers are fast, acurrate, and dumb; together they are unbeatable
We did this back in college, and it worked great.
The real genius of the system then comes in: whoever does their chores first gets to pick which ones to do, and whoever puts it off until the end has to do whatever's left. So there's a built-in incentive to do chores early, and no squabbling, because everyone agreed to the point rankings ahead of time.
Q: What does the "B." in Benoit B. Mandelbrot stand for? A: Benoit B. Mandelbrot
-> Specifically, if you express a value for the rooms as almost the same as your roommate, but slightly lower for the rooms he wants the most and slightly higher for the rooms he likes the least, I suspect their mechanism for overdemanded and underdemanded rooms will give you the slightly inferior rooms at a greatly reduced price
You'll only screw yourself that way. Suppose he values the first bedroom at $600 and the second at $500, because the first bedroom is better in some way.
You suggest going lower on the room he wants, so $550, and slightly higher for the room he doesn't want, so again $550. So you've said that you don't care which room you get. Since you don't care and he does, he'll get the better room. You said it's worth $550, he said $600, so he'll end up paying about $575.
Most of these algorithms automatically account for lying in the same way - the try to give you what you say you want. If you lie and say you want to sleep in the dumpster, you'll get what you asked for. The only time you won't get what you asked for is if someone else asked for the same thing.
What the algorithms don't cover well is if preferences vastly differ between people, AND you know what the other person's true preferences are. Suppose a brother and sister are dividing up a Barbie, a GI Joe, and a slice of cake. Brother can gain an advantage by OVER valuing the Barbie and under valuing the GI Joe, but not by too much - he doesn't want to actually end up getting the Barbie. He wants to end up with the "undesireable" GI Joe AND the cake. However , if the sister does the same thing, undervaluing the Barbie and overvaluing the GI Joe, they'll likely end up with what neither of them wanted.
If enough people start using tools like this and trusting game theorists, perhaps we will ultimately be able to get non-academics on board to fix our broken voting system. The American voting system was designed by people who thought slavery was fair, and was ultimately a compromise between people who thought land ownership should grant rights, and people who thought every white male should have equal rights.