Statistical Formulas For Programmers
The first example, "unbiased standard deviation" is mislabeled.  The estimator of the variance is unbiased but the square root of an unbiased estimator is not itself unbiased.  So it's not as nit-picky as it looks; it's either a brain fart or a hole in understanding (especially since the linked Wikipedia page discusses this issue)[1,2]<p>Not to be a dick, but getting the first example wrong like that doesn't inspire confidence in the rest of the post.<p>[1] <a href="https://en.wikipedia.org/wiki/Standard_deviation" rel="nofollow">https://en.wikipedia.org/wiki/Standard_deviation</a><p>[2] <a href="https://en.wikipedia.org/wiki/Unbiased_estimation_of_standard_deviation" rel="nofollow">https://en.wikipedia.org/wiki/Unbiased_estimation_of_standar...</a>