Coefficient of Variation

The coefficient of variation measures the variability of a series of numbers independent of the unit of measurement used for these numbers. In order to do so, the coefficient of variation eliminates the unit of measurement of the standard deviation of a series of numbers by dividing the standard deviation by the mean of these numbers. The coefficient of variation can be used to compare distributions obtained with different units, such as the variability of the weights of newborns (measured in grams) with the size of adults (measured in centimeters). The coefficient of variation is meaningful only for measurements with a real zero (i.e., “ratio scales”) because the mean is meaningful (i.e., unique) only for these scales. So, for example, it would be meaningless to ...