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

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

#111

Post by pinko »

yread wrote: post #8
seanhunter wrote: post #2

There's a nice presentation of the paper here https://www.youtube.com/watch?v=-QjgvbvFoQA In essence the effect comes from "precession" - the tendency of the flip to not be purely vertical but to have some wobble/angular momentum which causes it to flip in such a way as to spend longer on one side than the other. Depending on the technique this will have a greater or lesser effect on the fairness of the coin toss, ra…

link to the "wobble flip" trick https://youtu.be/-QjgvbvFoQA?t=325

I think you accidentally linked to the same video as the parent comment...

I bet this is the video you mean? https://www.youtube.com/watch?v=A-L7KOjyDrE

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

#112

Post by binarymax »

acyou wrote: post #96

The paper looks like it has a large sample size, but it actually has a sample size of only 48 testers/flippers. Some of the videos of those testers show very low, low-rpm coin tosses, we're talking only 1-2 flips. Where they also flipped thousands of times, presumably in the same way. So there is actually a very small sample size in the study (N = 48), where testers that don't flip properly (low rpm, low height, few…

1-2 flips should just invalidate the toss. Anyone in a real scenario upon seeing this would call shenanigans.

We need some minimum flippage for the toss to count.

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

#114

Post by its-summertime »

acyou wrote: post #96

The paper looks like it has a large sample size, but it actually has a sample size of only 48 testers/flippers. Some of the videos of those testers show very low, low-rpm coin tosses, we're talking only 1-2 flips. Where they also flipped thousands of times, presumably in the same way. So there is actually a very small sample size in the study (N = 48), where testers that don't flip properly (low rpm, low height, few…

> the role of some might have been more test subject than author

The reason is because it was used as incentive:

> Intrigued? Join us and earn a co-authorship

Per the linked youtube video.

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

#115

Post by kybernetikos »

KwisatzHaderack wrote: post #109
acyou wrote: post #96

The paper looks like it has a large sample size, but it actually has a sample size of only 48 testers/flippers. Some of the videos of those testers show very low, low-rpm coin tosses, we're talking only 1-2 flips. Where they also flipped thousands of times, presumably in the same way. So there is actually a very small sample size in the study (N = 48), where testers that don't flip properly (low rpm, low height, few…

> only 48 testers/flippers I assumed they did these coin flips were done using a machine. But I guess they wanted to test if human flippers because they wanted to make claims about the human coin flip phenomenon.

But if you get someone to flip a coin thousands of times for a boring reason, I would lose confidence that they are flipping in the same way a normal human would.

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

#116

Post by swores »

pinko wrote: post #111
yread wrote: post #8

Earlier quoted context omitted.

link to the "wobble flip" trick https://youtu.be/-QjgvbvFoQA?t=325

I think you accidentally linked to the same video as the parent comment... I bet this is the video you mean? https://www.youtube.com/watch?v=A-L7KOjyDrE

They linked to the same video, but to a specific timestamp within it - by adding '?t=325' to the URL, which tells Youtube to play the video from 5m25s rather than from the beginning.

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

#117

Post by lcnPylGDnU4H9OF »

salt4034 wrote: post #103
acyou wrote: post #96

The paper looks like it has a large sample size, but it actually has a sample size of only 48 testers/flippers. Some of the videos of those testers show very low, low-rpm coin tosses, we're talking only 1-2 flips. Where they also flipped thousands of times, presumably in the same way. So there is actually a very small sample size in the study (N = 48), where testers that don't flip properly (low rpm, low height, few…

> testers that don't flip properly I think that's the point. It shows that people don't usually flip properly, leading to biased results.

There is a [video presentation of the paper](https://www.youtube.com/watch?v=-QjgvbvFoQA) which does a good job of explaining the inspiration for the study within the first few minutes.

It sounds like what they were intending to study is the actual variance that is introduced, on average, by imperfections in throws conducted by humans. Unless that's mistaken, it's a fair point to consider the n=48 here. Did they discover an average that can be generalized to humans or just to those 48?

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

#118

Post by tomrod »

acyou wrote: post #96

The paper looks like it has a large sample size, but it actually has a sample size of only 48 testers/flippers. Some of the videos of those testers show very low, low-rpm coin tosses, we're talking only 1-2 flips. Where they also flipped thousands of times, presumably in the same way. So there is actually a very small sample size in the study (N = 48), where testers that don't flip properly (low rpm, low height, few…

Actually, I think it's more sound to approach this with clustered standard errors. Basic intuition is similar, but the sample size is what it is per person, and your observations aren't independent across draws but are across people.

https://en.m.wikipedia.org/wiki/Clustered_standard_errors

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

#119

Post by pkkkzip »

I noticed phenomenon in poker as well. Someone who runs well ahead of the crowd continues to do so seemingly even playing randomly with no thought into traditional poker theory.

For example, if a strong pair starts off with a bad beat then it tends to continue that trend. The word trend doesn't mean its going to happen but that its likely to continue the past.

When someone continues exploiting this trend they have seemingly "broken" the game, it no longer functions like a calculated game of odds and when somebody plays like a maniac (like in the first scenario i mentioned) there is seemingly no other defense than to wait until the trend breaks but no matter how seasoned a player is they cannot shake the past and its perceived likelihood of continuing.

This effect is rampant in stock market as well when there is seemingly less "random" reinforcements and belief in the crowd which without fail has given rise to black swans/massive collective drawdowns of the world war causing variety.

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

#120

Post by bambax »

acyou wrote: post #96

The paper looks like it has a large sample size, but it actually has a sample size of only 48 testers/flippers. Some of the videos of those testers show very low, low-rpm coin tosses, we're talking only 1-2 flips. Where they also flipped thousands of times, presumably in the same way. So there is actually a very small sample size in the study (N = 48), where testers that don't flip properly (low rpm, low height, few…

The real lesson is probably that if you're skilled enough, and/or train for long enough, you can influence the odds significantly without anyone ever noticing anything.
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