Re: Standard deviation
Standard deviation is basically the amount off your average you are on average.
The formula is as follows:
SD = {summation over y}[((x-y)^2)/(n-1)]^1/2]
-x is your average or mean
-y a complete set of individual values
-n is the number of individual values in your set
The formula looks far more complicated than it really is. It's necessary to square and then square root to get rid of negitives. If you didn't do that you would get zero everytime. '(n-1)' is used instead on 'n' to ensure that there are at least two numbers in the set.
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