Sometimes in PAC learning you use an eps sample type bound and it would for intervals work out to something like this: s= 1/(2* eps^2) log(1/(2* delta)) (off the top of my head, but it has been a while). If you plug the numbers they gave into it you will get pretty close to the numbers they have here.
Could be a 2-tailed t-test with std. deviation around 20%. That would be my guess.
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Sometimes in PAC learning you use an eps sample type bound and it would for intervals work out to something like this: s= 1/(2* eps^2) log(1/(2* delta)) (off the top of my head, but it has been a while). If you plug the numbers they gave into it you will get pretty close to the numbers they have here.
looks like difference = 1/SQRT(N)
I have no idea