Slashdot Mirror


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.

7 of 167 comments (clear)

  1. Commercialism. by ledow · · Score: 1, Insightful

    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.

  2. The ice cream method by drooling-dog · · Score: 5, Insightful

    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.

  3. Re:Toilet etiquette by Anonymous Coward · · Score: 3, Insightful

    Always down -- including the lid.

  4. Re:Toilet etiquette by Some_Llama · · Score: 5, Insightful

    it should ALWAYS be that the person sitting is in charge of making sure it is down.

    Men sit down to poop, i don't hear them ever argue about who left the seat up, they just check before sitting.

    common sense?

  5. solved: Up proves that it was raised. Also, forcin by raymorris · · Score: 5, Insightful

    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.

  6. Re:Toilet etiquette by Anonymous Coward · · Score: 2, Insightful

    your argument doesn't work even though it is logical

    most men are rational about everything except relationships

    most women are the opposite

    It is impossible to discuss anything rationally with a woman because she believes that her "feelings" have a value, and that value is infinite. Therefore the only thing of importance is that she gets the result that makes her "feel" good (usually involving the man making a lot of extra effort/resource expenditure)

    It doesn't "feel" good for her to have to make the effort to check the seat and possibly lower it. Therefore its the man's job to expend the effort to prevent her from "not feeling good".

    Once you realize that logic and reason are not useful tools when it comes to interacting with women then everything becomes much easier.

  7. Re:sibling fairness by radtea · · Score: 3, Insightful

    the algorith is old one, I remember it from Hugo Steinhaus's math book.

    That's a really nice description. I wish this was better known. But...

    The algorithm only works (in the sense of leaving the parties psychologically satisfied) if their preferences are transitive (that is, if they are not insane).

    In reality, even sane people's preferences change in pseudo-non-transitive ways as possibilities become actualities. So when Caleb gets the car, Adam is going to wish he'd valued it more highly, and so on. Our inner monkey won't be happy until it gets more than everyone else.

    There is also a considerable body of data showing that our ability to judge the value of stuff is very poor. Happiness research has been big on this, showing that most of what people think will make them happy is radically inferior to easily predictable things that will actually make them happy.

    So while the algorithm is beautiful and general and ought to be used wherever appropriate, it is not going to satisfy people, and it will then fall out of use because no one is going to say, "I am broken" when they can say "The algorithm is broken" instead.

    --
    Blasphemy is a human right. Blasphemophobia kills.