t-test on geometric means?

#1
I have 2 groups of dilutions (titres) that I would like to compare. The thing is, the mean for titres is usually the geometric one so I feel that I should not use a t-test as it is based on the arithmetic one, or should I?
Thanks for your help!
 

BGM

TS Contributor
#2
My little opinion: Geometric Mean is some how related to the product of random variables, in which can be thought as the sum of the log random variables and then having the exponentiation. While the Central Limit Theorem states that you may approximate the arithmetic mean by normal distribution, by the same analogy you may argue that the geometric mean can be approximated by the log-normal distribution. Of course, if you take the log of the geometric mean, then it is equivalent to the
arithmetic mean. But of course which distribution is better for approximation depends on the nature of your data.