Introduction
Quartiles
Percentiles
Quantiles
Standard Deviation and Variance
12. Units for variance and standard deviation

Instruction

The formula for variance uses squares. Therefore, the variance has different units than the data for which it was calculated. For example, if the data were measured in inches, the variance would be measured in square inches.

Interpreting the standard deviation in terms of units is easier because there are no squares. If, for instance, all observations are given in the Fahrenheit scale, the standard deviation will be too.