glm.nb()
to one that looks like the
output from
glm()
with a negative
binomial family. This allows it to be updated keeping the theta
parameter fixed.
glm.convert(object)
"negbin"
, typically
the output from
glm.nb()
.
"glm"
with negative
binomial family. The theta parameter is then fixed at its present
estimate.
Convenience function needed to effect some low level changes to the structure of the fitted model object.
quine.nb1 <- glm.nb(Days ~ Sex/(Age + Eth*Lrn), data = quine) quine.nbA <- glm.convert(quine.nb1) quine.nbB <- update(quine.nb1, . ~ . + Sex:Age:Lrn) anova(quine.nbA, quine.nbB)