In mathematics, the geometricmean is a mean or average, which indicates the central tendency or typical value of a set of numbers by using the product of their values (as opposed to the arithmetic mean which uses their sum). The geometricmean is defined as the th root of the product of numbers, i.
<mathematics> The Nth root of the product of N numbers.
If each number in a list of numbers was replaced with their
geometricmean, then multiplying them all together would still
give the same result. The geometricmean thus gives an
average "factor" in a context where numbers are multiplied
together, e.g. compound interest.
Wolfram (http://mathworld.wolfram.com/GeometricMean.html).
(2007-03-16)