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).
The variance is computed as the average squared deviation of each number from its mean. For example, for the numbers 1, 2, and 3, the mean is 2 and the variance is: . The formula (in summation notation) for the variance in a population is. where Î¼ is the mean and N is the number of scores. When the variance is computed in a sample, the statistic. (where M is the mean of the sample) can be used. SÂ² is a biased estimate of ÏÂ², however.