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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.
I'm sure the implicit assumption with this is that the actors are rational.
How would you assign a provable value to the room with a better view?
I think the requirement to have all your roommate's email addresses is the actual point of the website.
People can work out fair regimes. They can't spam their roommates easily enough, apparently.
dumb
with 2 roomates I've done things this way: have one person set the prices of each room and the other person can then pick which room they want. this has worked well. the main practical complication I've had in real life is when one person makes much more money than the other person. the well off person would likely be willing to spend far more than the "fair" price in this situation for the better room. I don't think there's any clear cut solution that works in every case.
Wtf, spliddit??? very original, losers.
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.
Fairness is for communists.
Sounds a lot like BillPin.
The best fairness concept i have ever seen involves two people trying to split one thing evenly, the way it works is one person does the splitting and the other gets to make the first choice of which half they want. this article reminds me of this concept.
You have a house, which has a total square feet. You have a total monthly rent. So there's dollar amount per square feet. Each person pays for their own room, the remaining square feet is split. so common / private is accounted for. why the fuck is this ground breaking. who's gonna stop someone from walking out. what sort of hipster fags are you sitting around a round table coming up with such a stupid name for a bunch of retarded ideas. why does the industry need more tech people with this garbage gets shitted out of the graduates mentally retarded brains. go burn in hell, faggots.
Once you have an algorithm that is provably fair, all you need to do is prove that the algorithm itself was chosen in a provably fair manner.
By another algorithm which is provably fair. With values which were chosen in a provably fair way. And so on. And so on.
As long as that chain of logic doesn't end with "BECAUSE I SAID SO NOW SHUT UP AND PAY YOUR SHARE!" then everybody should be satisfied by how fair everything is.
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.
too mny fckng vwls, shld hv calld it it splittr
the preceding comment is my own and in no way reflects the opinion of the Joint Chiefs of Staff
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
the main practical complication I've had in real life is when one person makes much more money than the other person. the well off person would likely be willing to spend far more than the "fair" price in this situation for the better room. I don't think there's any clear cut solution that works in every case.
Suppose the rent on the two bedroom place is $1,000. The "rich" roommate over bids as you suggest and says he'll pay $800 for the room on the left. Fine, that leaves the other roommate to cover only $200 for the other room. One can hardly complain about getting half of a $1,000 apartment for $200.
Cake-cutting algorithms, I love them. I've read parts of the book by Robertson and Webb and always wonder about unusual and new applications for them.
You're missing a vital alternative.
I'm male. I want the seat AND LID down so 1) nothing falls in, and 2) droplets and particles don't get launched out during a flush.
In my house, you will always find both the seat and lid down after I leave the bathroom. Also, nobody can bitch at me for leaving the seat up. It's as down as it can get.
Fair as defined by a rational decision theorist perhaps. The difficulty is assigning quantitative values to subjective experiences. Going to a movie costs 15 dollars, but is it "worth" 15 dollars? In rational decision theory this is easy to work out: rank all of the things you can do with 15 dollars, and the one that you want the most is the only one which is actually worth 15 dollars. I do not, however, think that this accurately describes human preference ordering. For this reason, fairness is as much cultural as it is mathematical. In fact, I wonder if we tend to think about what is "fair" as being that which is agreed to by all parties and is not "unfair". We have an in built notion of the concept of fairness (or at least some monkeys do, suggesting that we do), but is that internally defined by forms of fairness or negative unfairness? I feel like I am more quick to spot things that I would call "obviously unfair" than things which I would call "obviously fair"
I wish that people would stop trying to convert the subjective into mathematics.
You forgot the other option of the dilemma when there is retaliation. Put the seat and the cover down, always. That means both parties suffer the inconvienence of having to lift the seat (or at least the cover) every time.
There's also the "put things away when you're done" and "leave things the way you found it" and principles, both of which call for a closed lid.
Plus the "it's completely disgusting that my pets drink out of the toilet so please close the lid before they not only get sick but track toilet water everywhere" variant that doesn't apply to everyone, but is critical when it does apply.
The Quirkz Handbook of Self-Improvement for People Who Are Already Pretty Okay
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
It sounds like you're applying a rational process to women... Stop it.
Calling someone a "hater" only means you can not rationally rebut their argument.
Are you, in any way, implying that the government got the tax code right?
I've fallen off your lawn, and I can't get up.
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.
You're probably not serious, but just in case ...
Just sharing what little wisdom I've picked up over the years ..
We had cats and kids at one point. Letting cats (or any other dependent) drink water from a toilet is an act of stupidity. Eventually, they're going to catch something, and it may be very nasty -- even nasty enough that you might get it.
So... I set an alarm up that would go off in the kid's bathroom (they weren't allowed in ours) if the seat was up and the bathroom door was open.
The rules were: (1) if the alarm went off, they lost 10% of their allowance. (2) If the alarm was found to be disabled in any way, they lost their allowances permanently.
Worked great. The one time there was a problem with the alarm -- magnetic reed relay had stuck -- I was told before the kid left the bathroom. That seat and lid stayed down and the cats remained healthy. To this day, those kids (now in their 30's) don't leave seats and/or covers up. They know why, and they're properly habituated so it's not an issue.
I've fallen off your lawn, and I can't get up.
-> 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.
"All it takes is a pair of siblings to prove that there's no such thing as "provably fair," non-mathematically."
Obviously you did it wrong, you raised your kids wrong. They should be cooperating because they are fundamentally pack, team members and because they are mathematicians. You are illogical.
I wasn't serious. My actual strategy is to leave drips all over whichever restroom does not contain her makeup. She'll quickly stop using that restroom and only use "her" bathroom, the one with her makeup in it. Bonus points if her bathroom is also the guest bathroom.
Totally kidding- I want my woman to be happy when she has her pants down.
Complying beta faggot.
> The tray will prevent the seat from being raised all way to vertical and gravity will ensure it ends up down.
The clever woman forces me to hold the lid with one hand and my dick with the other? That's sure to improve my aim in her fancy-ass bathroom.
Animals won't get sick drinking toilet water.
Actually, I take that back. If you never cleaned the toilet then the pets won't get sick. But all those horrific additives and cleansers that people use in their toilets are guaranteed to kill off your beloved pets.
Congratulations to the researchers. They just re-invented PageRank.
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.
Sadly, after years of managing other people at work, I've seen the fact that most of those people didn't give a shit about "Fair". They wanted as much benefit for themselves that they could possibly weasel out of the system and to hell with everyone else.
But those people were always the first to scream UNfair!!! if they felt they weren't getting as much as they possibly could out of a situation, even if they were already getting MORE than everyone else... I've actually had people Lecture me on fairness, just for them to have me turn it around on them and PROVE that the way it was set up was perfectly fair and the way they were trying to get it was grossly UNfair to everyone else except them... They NEVER apologized when that happened and still tried to act like they were wronged somehow..
Needless to say people in general disgust the fuck out of me now.
"Provably fair" is not the same as "nobody would want to switch".
Since different people want different things (the basis for the algorithm), you can "Gerrymander" the fairness by giving one party just enough that they don't want to switch, and all the rest to the other party.
For example, divide 11 cakes with cream and 11 cakes without cream among two people where one of the two is lactose intolerant.
One gerrymandered "provably fair" division according to that definition gives the the lactose intolerant 6 cakes without cream, and the other 16 cakes.
So this one Shetland pony is eating away at a pile of hay in our yard and does not let the other pony at it. My SO puts up another pile in a different place in the yard. So the monopolizing pony pisses on his pile and goes to the other.
It's worth saying that this particular pony does not mind eating hay it pissed on itself, even when it's in its own stable. But that might be an acquired habit because of being able to secure food against horses higher in rank.
Try scenario of 2 rooms, 1 large, 1 small. Two tenants, one (A) much prefers the large room and is willing to pay 2/3 of the rent to get it; the other (B) wants to pay as little as possible.
Tenant A only gets asked once for their preference, for an even 50/50 split.
Tenant B picks the large room on the even split, and then the smaller room as it's cheaper, it then loops until back at a 50/50 split.
If you reverse the tenants, it gets closer to the 2/1 split.
Tried 3 tenents, and got strange results as well.
It does not treat all tenants the same (order entered matters), and does not allow for a preference of "the cheapest room", as that just ends up at an even split. Those with the higher budgets will pay less than their budget, those with the lowest budgets will be forced over their budget.
Two boys are arguing in a swimming pool. The mother comes and yells at them. She says each of you take half of the pool and stay in your half. One brother says,"That seems fair. " The other brother replies,"I'll take the top half."
...has anyone sent this url to the White House and Congress?
Something like that was done for real estate assessment in fiction (some Robert Heinlein novel) and also (I think) in reality (Singapore, perhaps). As I recall, in the fictional instance, there was another wrinkle: anyone could buy it for your assessment of its value (and had to pay the difference of the taxes for the previous 3 years, to boot). The purchase price you pay to the owner; the increment on the tax you paid to the government.
There's no time like the present. Well, the past used to be.
You and I completely had to AC these comments but it's true. His vagina is bigger, flappier, and stankier than his woman's.
"The only way to rectify our reasonings is to make them as tangible as those of the Mathematicians, so that we can find our error at a glance, and when there are disputes among persons, we can simply say: Let us calculate, without further ado, to see who is right."
The only way we found to divvy up cake / lasagna / ice cream / whatever, was to have one cut it, the other chose.
The only problem was if there was other than 2^n of us (if there is 2, 4, 8 etc, if you cut first you chose last, and all pieces are chosen, if there is other than 2^n, there is leftovers). We solved it by fighting for the leftover piece. My bigger brothers argued that was provably fair. I had to agree.
The only exception was the Dad Rule. If we got too rowdy, Dad would take it. Problem solved.
I am the Dad now.
It's good to be Dad.