Coefficient of variation - Wikipedia
https://en.wikipedia.org/wiki/Coefficient_of_variationWhen only a sample of data from a population is available, the population CV can be estimated using the ratio of the sample standard deviation to the sample mean : But this estimator, when applied to a small or moderately sized sample, tends to be too low: it is a biased estimator. For normally distributed data, an unbiased estimator for a sample of size n is: In many applications, it can be assumed that data are log-normally distributed (evidenced by th…