Thanks to Kit Baum, a new package, -fieller-, has been uploaded to SSC. The
package estimates confidence intervals for the quotient of two independent,
normally distributed samples of data. The method is based upon Fieller's
theorem.
The method, and the related method for correlated data (see Stata's official
-pkequiv-), have seen applications in pharmaceutics (evaluation of therapeutic
equivalency), pharmacy (U.S.P.-type assays for a medicine's potency) and health
economics (cost-effectiveness ratios), among other disciplines.
It has certain advantages over alternatives in that its confidence intervals
are considered "exact" when assumptions are met, and it is suitable for small
samples.
The first ado in the package, -fieller-, works on data in variables, and the
second, -fielleri-, is an immediate form of the command.
Bug reports, suggestions for improvement and the like may be e-mailed to me.
Joseph Coveney
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