standard deviation(redirected from Quadratic deviation)
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n. Abbr. SD
A statistic used as a measure of the dispersion or variation in a distribution or set of data, equal to the square root of the arithmetic mean of the squares of the deviations from the arithmetic mean.
(Statistics) statistics a measure of dispersion obtained by extracting the square root of the mean of the squared deviations of the observed values from their mean in a frequency distribution
a measure of dispersion in a frequency distribution, equal to the square root of the mean of the squares of the deviations from the arithmetic mean of the distribution.
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|Noun||1.||standard deviation - the square root of the variance|
statistics - a branch of applied mathematics concerned with the collection and interpretation of quantitative data and the use of probability theory to estimate population parameters
variance - the second moment around the mean; the expected value of the square of the deviations of a random variable from its mean value