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Fair coins tend to land on the side they started (2023)

researchgate.net

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Re: Fair coins tend to land on the side they started (2023)

#81

Post by outsidein »

two_handfuls wrote: post #61
outsidein wrote: post #39

Earlier quoted context omitted.

That is outside the preconditions of the paper: „if the person tossing the coin controls the bias“

Let me explain. You said: > Flip it twice. Once to determine which side is up at second throw. Reverse to counter bias at start of second throw. Then flip again for final result. Suppose I'm throwing the coin using your technique and I want to favor heads. I hold tails up for the first throw, making tails more likely. Then as per your rule, I put heads up for the second throw. Now, heads is more likely. Choose the op…

The paper is discussion regular people (not malicious people) tossing a coin, and under this precondition and assuming a fair (unbiased) coin.

It is not about intentional favoring on result.

Re: Fair coins tend to land on the side they started (2023)

#82

Post by mirekrusin »

whatever1 wrote: post #78

In other news, probabilities again used to prove whatever conclusions we were planning to present anyway. It is time to stop the show, probabilities cannot prove specifics. Aka they cannot prove that the coin I hold is fair or not. We can only get trends for big populations. There is only one way to prove if a coin is fair. Measure the actual thing that matters. In this case mass distribution. And if the measurement…

Also, there is fair _coin_ and fair coin _flip_, two different things.

Re: Fair coins tend to land on the side they started (2023)

#84

Post by hackernewds »

BiteCode_dev wrote: post #33
cgag wrote: post #24

I wouldn't be surprised if there is something to it, but I suspected they didn't use legitimate coin flips (because it seems like a large amount of people can't really flip a coin), and looking at the videos confirms it, at least for the flips done by Bartos: https://osf.io/6a5hy/ They're very low RPM and very low time in the air. Nothing I would accept for any decision worth flipping a coin for.

That's not tossing a coin, that's barely throwing it in the air. To me this kills the credibility of the entire study and of the authors. Sure, there may be something to it, but people will have a very different thing on their mind unless they check the video, which I wouldn't have done without your prompting. It's unlikely they don't understand how misleading it is. And somehow I have the intuition a proper coin tos…

a coin is likely to land on the same side. it was flipped from if it was tossed by a machine at low RPM and height consistently*

there's your paper

Re: Fair coins tend to land on the side they started (2023)

#85

Post by hackernewds »

cgag wrote: post #24

I wouldn't be surprised if there is something to it, but I suspected they didn't use legitimate coin flips (because it seems like a large amount of people can't really flip a coin), and looking at the videos confirms it, at least for the flips done by Bartos: https://osf.io/6a5hy/ They're very low RPM and very low time in the air. Nothing I would accept for any decision worth flipping a coin for.

but they did?

here's the video https://youtu.be/-QjgvbvFoQA?si=ZTT1LWWJC8T4LIQZ

Re: Fair coins tend to land on the side they started (2023)

#86

Post by [deleted] »

ComplexSystems wrote: post #3

I am curious how this changes if we condition on it flipping in the air at least once. Can we think of this result as a mixture distribution of a fair 50/50 chance of it flips at least once, and a delta function that is 100% at the side it started on, if not flipped at all?

[deleted]

Re: Fair coins tend to land on the side they started (2023)

#87

Post by BiteCode_dev »

hackernewds wrote: post #84
BiteCode_dev wrote: post #33

Earlier quoted context omitted.

That's not tossing a coin, that's barely throwing it in the air. To me this kills the credibility of the entire study and of the authors. Sure, there may be something to it, but people will have a very different thing on their mind unless they check the video, which I wouldn't have done without your prompting. It's unlikely they don't understand how misleading it is. And somehow I have the intuition a proper coin tos…

a coin is likely to land on the same side. it was flipped from if it was tossed by a machine at low RPM and height consistently* there's your paper

I'm sure you will find similar behavior with dice if you just gently let them fall from your hands instead of throwing them across the table.

This is silly.

Re: Fair coins tend to land on the side they started (2023)

#88

Post by roccomathijn »

hammock wrote: post #80
Vecr wrote: post #44

Earlier quoted context omitted.

Yeah, if I'm actually forced to use a coin instead of a computer system, I try to ping the thing off the ceiling and at least one wall (not in that order). Hitting various other things is a benefit, not a downside.

The guy in the grandparent YouTube video suggests shaking the coin in a closed hand (or better, a box) to randomize the starting side and then transferring it unseen to someone else to flip it Craps is also brought to mind where the dice have to bump the back wall

Let's abandon coin flipping in favour of coin shaking then

Re: Fair coins tend to land on the side they started (2023)

#89

Post by noman-land »

Haven't read the paper yet but this is so weird because when I was a kid I noticed this phenomenon myself. I noticed I could reliably flip a coin such that when it landed it would land on the same side as it was flipped from. I was getting like 80% accuracy and I didn't even know what I was doing to achieve it. I could just usually feel when I flipped it that I "did it right". I used it a couple times to win coin toss decisions but then sorta forgot about it and relegated it to a statistical fluke. It would be amazing of there was some merit to it.

Re: Fair coins tend to land on the side they started (2023)

#90

Post by BiteCode_dev »

thrw42A8N wrote: post #76
BiteCode_dev wrote: post #33

Earlier quoted context omitted.

That's not tossing a coin, that's barely throwing it in the air. To me this kills the credibility of the entire study and of the authors. Sure, there may be something to it, but people will have a very different thing on their mind unless they check the video, which I wouldn't have done without your prompting. It's unlikely they don't understand how misleading it is. And somehow I have the intuition a proper coin tos…

Is it unlikely? If I didn't read your comment I wouldn't see any problem there. I never saw anyone flipping a coin in a different way. It's just not done much around me.

If you claim to do a research on coin tossing, the minimum is to be aware on how people toss coin.

The whole purpose of tossing a coin is randomness, so of course you want high and fast.

If the result was that no matter how high and fast you throw is you get this bias, it would have been interesting.

But now you just say "if you do things badly, things don't work".

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