# standard deviation

- 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.

## Origin of standard deviation^{}

First recorded in 1920–25

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# standard deviation

- 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

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# standard deviation

*Symbol*

- A statistic used as a measure of the dispersion or variation in a distribution, equal to the square root of the arithmetic mean of the squares of the deviations from the arithmetic mean.

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Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.

# standard deviation

[stăn′dərd]

- A statistic used as a measure of the dispersion or variation in a distribution, equal to the square root of the arithmetic mean of the squares of the deviations from the arithmetic mean.

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Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

# standard deviation

In statistics, a measure of how much the data in a certain collection are scattered around the mean. A low standard deviation means that the data are tightly clustered; a high standard deviation means that they are widely scattered.

## Note

About sixty-eight percent of the data are within one standard deviation of the mean.

The New Dictionary of Cultural Literacy, Third Edition
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