# standard deviation

- (
*in statistics*) a measure of the scatter of observations about their arithmetic mean, which is calculated from the square root of the**variance**of the readings in the series. The arithmetic sum of the amounts by which each observation varies from the mean must be zero, but if these variations are squared before being summated, a positive value is obtained: the mean of this value is the variance. In practice a more reliable estimate of variance is obtained by dividing the sum of the squared deviations by one*less*than the total number of observations.**See also:**significance

*The new mediacal dictionary.
2014.*

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**standard deviation**— n. Statistics a measure of variability equal to the square root of the arithmetic average of the squares of the deviations from the mean in a frequency distribution … English World dictionary**Standard deviation**— In probability and statistics, the standard deviation is a measure of the dispersion of a collection of values. It can apply to a probability distribution, a random variable, a population or a data set. The standard deviation is usually denoted… … Wikipedia**standard deviation**— A standard deviation tells us how much specific examples vary from the average in a particular set. Thus, the larger the standard deviation, the more diverse/volatile are the examples. The more volatile the examples, the less predictable and… … Financial and business terms**Standard deviation**— The square root of the variance. A measure of dispersion of a set of data from their mean. The New York Times Financial Glossary * * * standard deviation standard deviation ➔ deviation * * * A statistical measure of the amount by which one… … Financial and business terms**Standard Deviation**— 1. A measure of the dispersion of a set of data from its mean. The more spread apart the data, the higher the deviation. Standard deviation is calculated as the square root of variance. 2. In finance, standard deviation is applied to the annual… … Investment dictionary**standard deviation**— (sd) a mathematical unit used to describe the spread or dispersion of a set of data. Each item in the data set has a deviation from the mean (the ordinary average) of the data. The standard deviation is computed by taking the squares of these… … Dictionary of units of measurement**standard deviation**— UK / US noun [countable] Word forms standard deviation : singular standard deviation plural standard deviations maths a number that shows how much smaller or larger a number in a set of numbers is from the average of the set … English dictionary**standard deviation**— noun the square root of the variance (Freq. 8) • Topics: ↑statistics • Hypernyms: ↑variance * * * ˌstandard deviˈation [standard deviation] … Useful english dictionary**standard deviation**— A measure of the dispersion of statistical data. For a series of n values x1, x2, xn, it is given by the formula →[(l n) ∑ (xi x)] where x is the average of the n values. The standard deviation of the returns from an investment can be used as a… … Big dictionary of business and management**Standard deviation**— A statistic used in *probability distribution models. In a *normal distribution of a *population of random items, the standard deviation represents the typical distance of an item from the population’s *mean value … Auditor's dictionary**standard deviation**— standartinis nuokrypis statusas T sritis biomedicinos mokslai apibrėžtis ↑Kintamojo reikšmių sklaidos apibūdinimas. Standartinis nuokrypis lygus teigiamai kvadratinės šaknies iš ↑dispersijos reikšmei. atitikmenys: angl. standard deviation… … Lithuanian dictionary (lietuvių žodynas)