On an Approximate Test for Homogeneity of Coefficients of Variation

  • B. M. Bennett
Part of the Experientia Supplementum book series (EXS, volume 22)


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. 


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Copyright information

© Springer Basel AG 1976

Authors and Affiliations

  • B. M. Bennett
    • 1
  1. 1.School of Public HealthUniversity of HawaiiHonoluluUSA

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