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Originally Posted by 10intheCrunch
Ummm, OK I was looking over it again, and...are you sure you got the standard deviations right? There are several SDs that are greater than the mean score, which seems to ring wrong with me (I haven't taken stats but +- 1 SD is about 2/3 of the data, right?).
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The standard deviation is only 2/3 of the data when the data is gaussian (also called normal or bell shaped curve). The score's of most team's matches is no where near a bell shaped curve, and so that doesn't hold. I checked the numbers for team 970 at OH, which was one of the teams where the standard deviation was higher then the mean, and the calculations were correct.
(standard deviation)^2 = (sum(xn - mean)^2)/(n-1)
You can use this webpage to do the calculations for you:
http://www.physics.csbsju.edu/stats/...NROW_form.html and this page has explanations of a bunch of different statistical measurments:
http://www.physics.csbsju.edu/stats/descriptive2.html