On Wed, 18 Oct 2006, SCHMERA D?nes wrote:
> Dear All,
>
> I would like to run a generalized linear mixed model with the software R
(one categorical predictor, one random factor, the distribution of the dependent
variable is binomial, and the link is logit). Thereafter, I would like to
perform multiple comparisons (post hoc test) among the groups of the categorical
predictor.
>
> Is it possible with the software R?
>
yes and no. There is the `multcomp' package available but the CRAN version
is limited to linear models (more or less). However, I'm currently working
on a re-implementation which has solutions for your problem and much
more :-)
For the time being, the development version is available from
http://www.imbe.med.uni-erlangen.de/~hothorn/multcomp2
The basic steps would be as follows:
### fit logistic regression model> my.glm <- glm(response ~ myfactor, data = <mydata>, family =
binomial())
### set up linear hypothesis for coef(my.glm) corresponding to all-pair
### comparisons> library("multcomp2")
> gh <- glht(my.glm, linfct = mcp(myfactor = "Tukey"))
### simultaneous confidence intervals with plots> confint(gh)
> plot(confint(gh))
Hope that helps.
Torsten
> Are traditional methods of multple comparisons (for instance Tukey test)
adequate for this purpose or not? Does Tukey test consider the binomial
dsitribution of the dependent variable and the logit link?
>
> I am waiting for your answer,
> Denes Schmera
>
> ______________________________________________
> R-help at 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
> and provide commented, minimal, self-contained, reproducible code.
>