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the square root of the variance

the square root of the variance

(SD) A measure of the range of values in a set ofnumbers. Standard deviation is a statistic used as a measureof the dispersion or variation in a distribution, equal to thesquare root of the arithmetic mean of the squares of thedeviations from the arithmetic mean.The standard deviation of a random variable or list of numbers(the lowercase greek sigma) is the square of the variance.The standard deviation of the list x1, x2, x3...xn is given bythe formula: sigma = sqrt ( ( (x1- (avg(x)))^2 + (x1- (avg(x)))^2 + ... + (xn(avg(x)))^2)/n)The formula is used when all of the values in the populationare known. If the values x1...xn are a random sample chosenfrom the population, then the sample Standard Deviation iscalculated with same formula, except that (n-1) is used as thedenominator..["Barrons Dictionary of Mathematical Terms, second edition"].