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## Definition of *standard deviation*

1

**:**a measure of the dispersion of a frequency distribution that is the square root of the arithmetic mean of the squares of the deviation of each of the class frequencies from the arithmetic mean of the frequency distribution also**:**a similar quantity found by dividing by one less than the number of squares in the sum of squares instead of taking the arithmetic mean2

**:**a parameter that indicates the way in which a probability function or a probability density function is centered around its mean and that is equal to the square root of the moment in which the deviation from the mean is squaredKeep scrolling for more

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standard deviationTime Traveler for

standard deviation## The first known use of

standard deviationwas in 1894See more words from the same year