How to create an unfair coin and prove it with math (2011)
izbicki.me
izbicki.me
You can load a die but you can’t bias a coin - https://www.stat.berkeley.edu/~nolan/Papers/dice.pdf
if you let the biased coin bounce and flop around, e.g. by throwing it onto a table or into the ground, it will show biased results.
thats what I read in your quoted report.
Is this a parody of statistical driven thinking?
The coins are clearly biased from the first bent coin on. It just takes a more extreme bias for the statistics to "prove" the bias assuming no other information using only 100 flips.
But we have other information: you know you bent the coins...
The statistics are not useful for confirming the bias. Rather they are useful for finding "how much cheating" you can push before the statistics alone are enough to get you beat up.
I mean, what were you expecting? He flipped a coin 600 times. his findings aren't going to be groundbreaking if he did it 6.000 times.
The stats in the post is mostly a commentary on the phenomenon of statistical power. It may also be a commentary on how the angle of the bend is non-linearly related to coin flip bias. I did find that bit to be unexpected. Although given the wide sampling distribution due to the low N, this could easily be variance.
Because 3rd coin flipped 41 out of 100, at level 0.95 the confidence interval still contains 0.50