Contribution to Applied Statistics pp 169-171 | Cite as

# On an Approximate Test for Homogeneity of Coefficients of Variation

## Summary

The coefficient of variation (c. v.) *ζ* = *σ*/*ξ*, or ratio of standard deviation to mean (*ξ* > 0), is a useful parameter and measure of variability in certain situations since it is expressed in absolute units. Thus in comparing results on repeated clinical data when *k* (≥ 2) different measurement techniques are utilized in analyzing the same or paired specimens, it is of interest to compare the corresponding sample c. v.’s *z* _{1}, ... , *z* _{k} respectively for the *k* techniques. For this situation the following note presents a test which is based on McKay’s approximation [4] to the distribution of the sample c. v. for the normal distribution, and utilizes Pitman’s method [5] for the hypothesis of equality of scale parameters of Gamma variates.

## Key Words

Coefficients of variation in independent samples McKay’s approximation Pitman’s test for scale parameters.## Preview

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## References

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