standard deviation

American  

noun

Statistics.

1. 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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standard deviation British  

noun

1. 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 Scientific  

/ stăn′dərd /

1. 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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standard deviation Cultural  

1. 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.

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Discover More

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

Etymology

Origin of standard deviation

First recorded in 1920–25

Compare meaning

How does standard-deviation compare to similar and commonly confused words? Explore the most common comparisons:

• standard deviation vs. standard error

Example Sentences

Standard deviation measures how much variation there is in your sample.

From Scientific American • Sep. 7, 2023

The Standard deviation of the sampling distribution is further affected by two things, the standard deviation of the population and the sample size we chose for our data.

From Textbooks • Nov. 29, 2017

Standard deviation is a statistical measurement of variation.

From The Wall Street Journal • Oct. 20, 2016

Standard deviation is the square root of variance, so the standard deviation of the sampling distribution is the standard deviation of the original distribution divided by the square root of n.

From Textbooks • Sep. 19, 2013