Thread: Calculating standard deviation of X hands
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Old 11-19-2007, 05:36 PM
tame_deuces tame_deuces is offline
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Default Re: Calculating standard deviation of X hands
SD is the square root of the average squared difference between data and the mean.

So if you got {8,16,4,20}, the mean is 12. The deviations are {-4,4,-8,8} which squared are {16,16,64,64} and the square root of that is {4,4,8,8} and the average of that is 6. So your SD is 6.

I just usually think of it as the average of all the (absolute) distances to the mean - in your case for all X hands. Since I haven't done proper numbers in years and I probably even botched this minimal thing up.
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