The paper shows some significant evidence that human coin flips are not as fair as I would have expected (plus probably a bunch of people would agree with me). There’s always some probability that this happened by chance, but this is pretty low.

Of course, we should be able to build a really accurate coin flipping machine, but I never would have expected such a bias for human flippers.

This is why science is awesome and challenging your ideas is important.

Edit: hopefully this is not too wrong a place, but Lemmy is small, and I didn’t know where else I could share such an exciting finding.

  • wmassingham@lemmy.worldEnglish
    311·
    1 year ago

    tl;dr:

    The standard model of coin flipping was extended by Persi Diaconis [12] who proposed that when people flip a ordinary coin, they introduce a small degree of ‘precession’ or wobble—a change in the direction of the axis of rotation throughout the coin’s trajectory. According to the Diaconis model, precession causes the coin to spend more time in the air with the initial side facing up. Consequently, the coin has a higher chance of landing on the same side as it started (i.e., ‘same-side bias’).

    “Higher chance” being 50.77% to land on the same side it started from. But this varies by person; apparently some people introduce more precession than others. But even if you could figure out how to do it reliably, I wouldn’t bet the farm on it.

    • PetDinosaurs@lemmy.worldOPEnglish
      42·
      1 year ago

      I’m curious why you don’t think this is significant?

      This is a pretty high house edge (or whatever you want to call it) for a game that seems the most fair as possible.

      No casino games are that fair.

      As is discussed elsewhere in this thread, you could probably practice and get that higher.

      • beeng@discuss.tchncs.deEnglish
        2·
        1 year ago

        Where are coins flipped multiple times in order to gain such value from doing so? I can only think of 2up being played in Australia, 1 day per year and they don’t flick it with their thumb, so…

        Where is the “house” gaining so much?

        • PetDinosaurs@lemmy.worldOPEnglish
          44·
          1 year ago

          You can bet on dice and coin flips.

          “I bet you a dollar that my coin flip will come up heads?”

          This research suggests that this is not only profitable, but can be improved upon.

          Edit: so weird. Why would such a simple and correct statement be controversial? I would’ve thought that betting on heads or tails was not this far out of fair coin odds.