Abstract
In the practical situation, the coefficient of variation is used as a measure of stability of the product quality or the operation performance, and also it has many other applications. This paper presents approximate distribution of the coefficient of variation which can be calculated from random samples of size n having a normal universe. The approaches employed here are (1) normal approximatiom and (2) χ approximation, since the moment method can not be applied when n is small. The results are confirmed by means of simulation experiment. An application of this approximate distribution is exhibited in the process of analyzing the sample size determination to assure the desired level of precision. We analyze the distribution of square of the coefficient of variation by the same approaches. The necessary condition is also given that χ2 distribution is available for a practical and convenient approximation to the square of coefficient of variation.
