On Sunday, 18 April 2004 at 0:52:19 +0200, Peter Dalgaard wrote: > Eric Cheney <[EMAIL PROTECTED]> writes: > > > Could someone tell me how to access the log likelihood > > of a poisson model? I've done the following.... > > > > <BEGIN R STUFF> > > > > freq.mod <- glm(formula = nfix ~ gls.gls + pol.gls + pol.rel + rac.gls + > > rac.pol + rac.rac + rac.rel + white + gls.gls.w + pol.gls.w + pol.rel.w > > + rac.gls.w + rac.pol.w + rac.rac.w + rac.rac.w + rac.rel.w, family = > > poisson, data = Complex2.freq, offset = lnoffset) > > > > summary(freq.mod) > > anova(freq.mod) > > > > <END R STUFF> > > > > And that's great; but I need the log likelihood. > > > > Anyone know? > > The deviance will not suffice? > > sum(dpois(nfix, fitted(freq.mod), log.p=T)) > > should do the trick otherwise.
Thank you, that did the trick. I should note that the method doesn't work when I have a noninteger in Y. I'm doing a "log linear" analysis of a cross table, and one of the cells of the cross table has a zero value. I put a .5 in that cell. With the ".5 analysis" the above method doesn't work. So I had to revert to an analysis with a zero cell to make it work. Which has some problems. So I'm still left looking for the log likelihood of the ".5 analysis". I've had success with Stata using this method, but not R. Thanks again. -- <Eric Cheney> [EMAIL PROTECTED] http://sociostat.org/eric/ ______________________________________________ [EMAIL PROTECTED] mailing list https://www.stat.math.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html
