Forest Products Laboratory
A Confidence Interval
on the Ratio of the Coefficients of
Variation of Two Normally Distributed Populations
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This page is a form for calculating a
confidence interval on the ratio of the
coefficients of variation of two normally
Here is FORTRAN
source code for
a standalone program that calculates the confidence interval.
also have programs that do the following:
The theory behind these programs is described in three publications:
Confidence Bounds for Normal and Lognormal Distribution Coefficients of Variation,
2003, Research Paper 609, USDA Forest Products Laboratory, Madison, Wisconsin.
Confidence Bounds and Hypothesis Tests
for Normal Distribution Coefficients of Variation,
2007, Research Paper 638, USDA Forest Products Laboratory, Madison,
- Verrill, S. and Johnson, R.A. (2007). "Confidence Bounds and
Hypothesis Tests for Normal Distribution Coefficients of Variation."
Communications in Statistics -- Theory and Methods, Volume 36,
Number 12, pages 2187-2206.
For questions or comments about this Web page, please contact Steve Verrill at
[FPL Statistics Group]
Last modified on 9/9/09.
As of last midnight, this page had been accessed