Statistics. The geometric mean is the nth root of the product of the scores. It is used to minimize the effects of extreme values (e.g. when averaging growth rates). For example, the geometric mean of the scores 1, 2, 3 and 10 is the fourth root of 1 × 2 × 3 × 10 which equals 2.78, in comparison to the arithmetic mean of 4.
See also arithmetic mean.