The
mean absolute difference is a measure of statistical dispersion equal to the average
absolute difference of two independent values drawn from a
probability distribution. A related statistic is the
relative mean absolute difference, which is the mean absolute difference divided by the
arithmetic mean, and equal to twice the
Gini coefficient. The mean absolute difference is also known as the
absolute mean difference (not to be confused with the
absolute value of the
mean signed difference) and the
Gini mean absolute difference. The mean absolute difference is sometimes denoted by Δ or as MD.