Wikipedia’s page for Standard Deviation presents a formula for rapidly calculating the standard deviation of a growing set of numbers:
 Qk = Qk-1 + (xk – Ak-1)(xk – Ak) where xk is the kth element in the set and Ak is the mean of the first kth numbers.
The standard deviation squared of the first n numbers of a set is Qn / n.
From this, it is easy … Read more
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Figured I’d compile this list after seeing several cheaters that … Read more