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

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392 points seanhunter | 1 comments | 19 Nov 24 09:03 UTC | HN request time: 0.208s | source
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cgag ◴[19 Nov 24 15:25 UTC] No.42184472[source]▶
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.

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TremendousJudge ◴[19 Nov 24 15:42 UTC] No.42184698[source]▶
This was my first objection as well. However, if most people flip coins like that, then the measurements are valid -- the conclusions are about what average people will do, not a perfect mechanical coin flip. Otherwise you're falling in the no true coin flip fallacy.
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Vecr ◴[19 Nov 24 15:46 UTC] No.42184742[source]▶
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.
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1. layman51 ◴[20 Nov 24 02:46 UTC] No.42190401[source]▶
Your point about the coin hitting other things to be more unpredictable reminded me of an interesting blog post[1] about generating cryptographically secure random numbers. The memorable part for me is the suggestion of using five coins of different shapes and sizes so they get shaken a consistent number of times in a large cup.

[1]: https://blog.sia.tech/generating-cryptographically-secure-ra...