Coefficient of Variation

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Coefficient of Variation
Message posted by E. Sanchez (via 63.206.246.74) on September 14, 2001 at 12:53 PM (ET)

In order to calculate the COV between two pooled sets of data the maximum expected variation must be obtained. The formula I am using is the pooled variation multiplied by the degrees of freedom divided by the chi-squared value. Does anybody out there know what the correct formula for maximum expected variation should be using the chi-squared probability chart? Any informationn would be very very helpful.

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Re: Coefficient of Variation
Message posted by Jack Tomsky (via 208.249.113.130) on September 14, 2001 at 5:55 PM (ET)

The coefficient of variation (CV) is the ratio of the standard deviation to the mean. The sample CV is distributed as inversely proportional to a noncentral t distribution.

I'm not sure what your application is, but you can use that fact to obtain confidence limits, estimated percentiles, etc.

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