What is the meaning of Samona? How popular is the baby name Samona? Learn the origin and popularity plus how to pronounce Samona
Variance. Variance (Ï 2) is a measure of the dispersion of a set of data points around their mean value. In other words, variance is a mathematical expectation of the average squared deviations from the mean. It is computed by finding the probability-weighted average of squared deviations from the expected value. Variance measures the variability from an average (volatility).
Calculate the mean, x. 1  Write a table that subtracts the mean from each observed value. 2  Square each of the differences. 3  Add this column. 4  Divide by n -1 where n is the number of items in the sample This is the variance. 5  To get the standard deviation we take the square root of the variance.