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

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21–30 of 193 posts

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

#21
post #4

This is clearly the law of conservation of reality at work. Likewise, when you hear a word for the first time suddenly you hear it five times in a row. Or if you see somebody once you suddenly start running into them all over the place. It's because it's cheaper to repeat past realities than to create new ones.

Does this explain the rarity of antimatter?

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

#22
post #17

This is probably just because the coins aren’t actually fair. If the coin is slightly biased towards heads, the first throw is more likely to heads, and so are all subsequent throws. Same for tails.

That's the opposite of what the paper says. If the coin was biased you'd expect it to land on heads more often regardless of what side it starts on. The coins land on the side they start on more often.

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

#23

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.

That only works for a fixed bias, it's gameable if the person tossing the coin controls the bias.

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

#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.

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

#25
post #22
post #17

This is probably just because the coins aren’t actually fair. If the coin is slightly biased towards heads, the first throw is more likely to heads, and so are all subsequent throws. Same for tails.

That's the opposite of what the paper says. If the coin was biased you'd expect it to land on heads more often regardless of what side it starts on. The coins land on the side they start on more often.

No, first of all due to imperfections in the manufacture of real coins, there are actually no fair coins. Also the bias in the probability affects the first throw as well as all the rest. If your dataset is composed of first throws/rest of the throws, you’re going to see they are correlated.

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

#26
post #18
post #17

This is probably just because the coins aren’t actually fair. If the coin is slightly biased towards heads, the first throw is more likely to heads, and so are all subsequent throws. Same for tails.

That's not the problem. You can test that by using a highly secure random number generator, e.g. /dev/random in Linux, to select the initial side. Keep track of that initial side, record the side it lands on. This paper shows a same-side bias, not a heads bias.

A same side bias is either a heads bias or a tails bias.

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

#27
This has been commonly known by magicians for decades. I doubt that any single magician had conducted 350k flips, but I know I personally did ~2,500 to test the effect when I was a kid.

And I'm sure if you got 30 magicians together to pool data we'd have a meta-analysis of about this size but with experiments a century ago

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

#28
post #14
post #10

Earlier quoted context omitted.

Oh sure, let's doubt the evidence of our senses in favor of convention. That's good science.

How good are you at Bayesian statistics, conditionalization, and understanding various biases? The simulation here should be good (it's better than mine).

Next you'll cite Bible verse.

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

#29

Easy way to get a fair result from an unfair coin toss: Flip the coin twice in a row, in this case starting with the same side facing up both times, so it's equally unfair for both tosses. If you get heads-heads or tails-tails, discard and start over until you get either heads-tails or tails-heads, which have equal probabilities (so you can say something like HT = "heads" and TH = "tails"). This works even if the coi…

Importantly - you don't have to know the odds of the coin ahead of time, or which side is more likely. You only need to know that it is consistent.
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