Functions are provided that implement the
use of the Fieller's formula methodology, for
calculating a confidence interval for a ratio of
(commonly, correlated) means. See Fieller (1954)
. Here,
the application of primary interest is to studies
ofinsect mortality response toincreasing doses
of a fumigant, or, e.g., to time in coolstorage.
The formula is used to calculate a confidence
interval for the dose or time required to achieve
a specified mortality proportion, commonly 0.5
or 0.99. Vignettes demonstrate link functions
that may be considered, checks on fitted models,
and alternative choices of error family. Note
in particular the betabinomial error family.
See also Maindonald, Waddell, and Petry (2001)
.