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variance

Expectation of the squared deviation of a random variable from its mean

Entitydescriptive statistic moment of order rQ175199

Instance of: descriptive statistic
, moment of order r

Overview

From Wikipedia, the free encyclopedia · Read full article · Text CC BY-SA 4.0

In probability theory and statistics, variance is a measure of dispersion, meaning it is a measure of how far a set of numbers are spread out from their average value. It is defined as the expected value of the squared deviation from the mean of a random variable. The standard deviation is the square root of the variance. Technically, it is the second central moment of a distribution, and the covariance of the random variable with itself, and it is often represented by ⁠⁠, ⁠⁠, ⁠⁠, ⁠⁠, or ⁠⁠.

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All data

39 statements · 13% with external sources · numbers in brackets are citations

Opposite of: precision
Main Wikidata property: variance of a probability distribution
Different from: sample variance
Defining formula: V(X) = E\left(\left(X - E(X)\right)^2\right)
In defining formula: V(\cdot) symbol represents: variance
X symbol represents: random variable
E(\cdot) symbol represents: expectation
Quantity symbol (LaTeX): V(X)
\sigma^2
Invariant under: translation
Partially coincident with: variance

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13%

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Source last edited October 6, 2026. AIDB refreshes this page daily.

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AIDB. (2026). variance (Q175199). Retrieved from https://aidb.si/e/variance-Q175199