What formula is used to find a sample variance?

The formula to find a sample variance is as follows: s squared equals sigma(x-x-bar)squared over n-1. Working out the problem involves determining the mean, subtracting the mean for each number and then squaring the result and then determining the average of the squared differences.

In math, variance will always be a nonnegative. In statistics and probability, variance tells someone how spread out a set of numbers are. All values are identical when there is a variance of zero. Those performing statistics use the sample mean to estimate the population mean. It works to measure location and the symbol is usually an x-bar.