glmmPQL is not documented to work with groupedData objects, so that's your
mistake.
See ?glmmPQL and supply a valid formula for random.
On Mon, 14 Apr 2003, kjetil brinchmann halvorsen wrote:
> I am encountering the following problem, in a multilevel analysis,
> using glmmPQL from MASS. This occurs with bothj rw1062 and r-devel,
> respectively with nlme versions 3.1-38 and 3.1-39 (windows XP).
>
> > S817.mod1 <- glmmPQL( S817 ~
MIEMBROScat+S901+S902A+S923+URBRUR+REGION+
> +
> S102+S103+S106A+S108+S110A+S109A+S202+S401+S557A+S557B+
> + YHOGFcat, data=Hogares, random= ~1,
> family=binomial,
> + na.action=na.omit)
> iteration 1
> Error in getGroups.data.frame(dataMix, groups) :
> Invalid formula for groups
> > getGroupsFormula(Hogares)
> ~ID08
>
> Hogares is a groupedData object. The only non-default thing I have
> done is to use order.groups=FALSE in groupedData, since the response
> is a factor and the max ordering function does not apply.
>
> What is wring here?
--
Brian D. Ripley, ripley at stats.ox.ac.uk
Professor of Applied Statistics, http://www.stats.ox.ac.uk/~ripley/
University of Oxford, Tel: +44 1865 272861 (self)
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