Calxsolver
Subject:  Statistics

Standard deviation

A measure of how spread out the values in a data set are around the mean.

The standard deviation is the square root of the variance. Population standard deviation divides the sum of squared deviations by n; sample standard deviation divides by n − 1 to correct bias when estimating from a sample.

Formula

σ = √( Σ(xᵢ − x̄)² / n )

Used in

Descriptive Statistics Mean, median, mode, range and standard deviation. Z-Score Calculator Standardize a value against a mean and standard deviation. Normal Distribution Calculator Probabilities for a normal distribution N(μ, σ). Confidence Interval Calculator Confidence interval for a population mean.

See also

Mean The arithmetic average of a set of numbers — their sum divided by the count. Z-score The number of standard deviations a value lies above or below the mean.