Variance is a statistical measure that tells us how measured data vary from the average value of the set of data. In other words, variance is the mean of the squares of the deviations from the arithmetic mean of a data set. More About Variance. Variance is the square of the standard deviation.What does variance mean in a data set?
Variance is a measurement of the spread between numbers in a data set. The variance measures how far each number in the set is from the mean.