Variance (regarding to the arithmetic mean)

Description

The variance measures how far a set of numbers of n equally likely values is spread out. A small variance indicates that the data tend to be very close to the mean (expected value) and hence to each other, while a high variance indicates that the data are very spread out around the mean and from each other.The arithmetic mean of the values must be precalculated. ( Arithmetic mean is the sum of a collection of numbers divided by the number of numbers in the collection).
Variance is the square of the standard deviation.

Related formulas

Variables

σVariance (dimensionless)
vThe individual values of a data series (dimensionless)
XiThe average of the values of the data series (dimensionless)
nThe number of occurences (dimensionless)