> From: Douglas Bates > > Henric Nilsson wrote: > > On Mon, 2005-05-02, 17:24, Douglas Bates wrote: > > > > > >>weihong wrote: > >> > >>>Can GLMM take formula derived from another object? > >>> > >>>foo <- glm (OVEN ~ h + h2, poisson, dataset) > >>> > >>># ok > >>>bar <- GLMM (OVEN ~ h + h2, poisson, dataset, random = > list (yr = ~1)) > >>> > >>>#error > >>>bar <- GLMM (foo$formula, poisson, dataset, random = list > (yr = ~1)) > >>>#Error in foo$("formula" + yr + 1) : invalid subscript type > >> > >>That won't work without some tweaking of the GLMM function. In the > >>0.95-1 and later versions of the lme4 package the > capabilities of GLMM > >>have been folded in to the lmer function and you would need > to fit that > >>model as > >> > >> lmer(OVEN ~ h + h2 + (1|yr), dataset, poisson) > >> > >>anyway. > > > > > > I don't have access to the "White Book" right now (or R, > for that matter), > > but doesn't it say that something like the following works? > > > > fit.lm <- lm(y ~ x) > > fit.glm <- update(fit.lm, class = "glm") > > > > But this isn't implemented in R, right? If one can make a > wish, it would > > be really nice being able to (using weihong's example): > > > > bar <- update(foo, . ~ . + (1|yr), class = "lmer") > > > > > > //Henric > > It's not very convenient from the point of view of dispatch. The > dispatch rules are such that the update method for the lm or glm class > would need to be aware of the lmer class to be able to do > this. The lm > and glm classes predate lmer by a long time.
In that case, wouldn't lmer also need to be in "stats" (or somewhere "stats" can import from)? Best, Andy ______________________________________________ R-help@stat.math.ethz.ch mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html