We'd like to use analytics cookies to understand which symbols people look up, so we know what to research next. They are not used for advertising and we set none of them unless you say yes. What we store.
The letters Var, or a squared sigma, measuring spread.
Also known as: Var, Sigma squared, Variance operator
Variance measures how far a random variable spreads from its mean, in squared units. Because the units are squared it is not directly comparable with the data, which is why the standard deviation — its square root — is what usually gets reported.
Denotes the variance of a random variable: the expected squared deviation from its mean.
Contexts: Mathematics
Carries squared units, so it is not on the same scale as the data and is usually reported through its square root instead.
Contexts: Mathematics
Is written as a squared sigma for a population and as s squared for a sample, a distinction that changes the divisor used to compute it.
Contexts: Mathematics
Three lowercase letters followed by a bracketed variable, or a Greek letter with a small raised numeral two.