Dear Georges and Splus-users,
I also asked the same kind of question in June 2003, and got no answer:
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Dear Splus users,
I fitted a GLM with a Poisson distribution. The model involves 3 factors
and all interactions. I am interested in testing effects involving 2
factors and their interaction, say A*B.
I carry out multiple comparisons on differences between adjusted means
on A*B (A+B+A:B), but I am interested by tests on the scale of the
original response.
My first question is : how to use predict.glm et multicomp for
calculating adjusted means and testing several contrasts involving
differences on these adjusted means?
If this implies using multicomp.default, what vmat and nn should be
specified ?
Second question:
May I use summary.aov on a GLM object (to have Type III sums of squares)
(are these computations appropriate for GLM?)
Third question:
Because I present GLM results along with ANOVA results, I would like to
report an equivalent of R2 for GLM. I was considering using :
(null deviance - residual deviance)/null deviance
Is this appropriate ? Is there a better measure ?
Thank you very much for your help,
#####
I hope this time we may get some
Dominique
Georges KUNSTLER a écrit:
I fitted a GLM with a binomial distribution. The model involves 3
factors (with two levels) and all interactions.
How to use multicomp for calculating adjusted means and testing
differences on these adjusted means?
Is it working with glm.objects or not?
There is the same question in s-news archive, but there are no answers.
Thank you very much for your help,
Georges Kunstler
Ph.D. Student
Centre d'Ecologie Fonctionnelle et Evolutive. CNRS
Département Dynamique des Systèmes Ecologiques
1919 Route de Mende F-34293 Montpellier Cedex 5
FRANCE
Tel : 33 4.67.61.33.05
Fax : 33 4.67.41.21.38
http://www.cefe.cnrs-mop.fr/dse/
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Laboratoire MAERHA
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E-mail: dpellet@ifremer.fr
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Fax: 33 2 40374075
http://www.ifremer.fr/maerha/
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