Help! Being a bit of a novice, please bear with me if this is a stupid question! I am trying to fit a saturated model to some count data that I have: model<-glm(COUNT~SP*LOC*COL*TIME*TREAT,poisson) but R keeps on crashing and coming up with (occasionally before crashing) an error that states: Algorithm did not converge in: (if(is.empty.model(mt)) glm.fit.null else glm.fit)(x = X, y = Y, What am I doing wrong? Thanks Laetitia
"glm" tries to maximize the likelihood. In certain cases, the likelihood is maximized at infinite. This may be the case with your saturated model. I suggest you think carefully about what you want to do, and then fit one or several models that avoid this problem. hope this helps. spencer graves Laine, Laetitia wrote:> Help! Being a bit of a novice, please bear with me if this is a stupid > question! > > I am trying to fit a saturated model to some count data that I have: > > model<-glm(COUNT~SP*LOC*COL*TIME*TREAT,poisson) > > but R keeps on crashing and coming up with (occasionally before crashing) an > error that states: > > Algorithm did not converge in: (if(is.empty.model(mt)) glm.fit.null else > glm.fit)(x = X, y = Y, > > What am I doing wrong? > > Thanks > > Laetitia > > ______________________________________________ > R-help at stat.math.ethz.ch mailing list > https://www.stat.math.ethz.ch/mailman/listinfo/r-help
Dear Laetitia, At 11:04 AM 4/28/2003 -0500, Laine, Laetitia wrote:>Help! Being a bit of a novice, please bear with me if this is a stupid >question! > >I am trying to fit a saturated model to some count data that I have: > >model<-glm(COUNT~SP*LOC*COL*TIME*TREAT,poisson) > >but R keeps on crashing and coming up with (occasionally before crashing) an >error that states: > >Algorithm did not converge in: (if(is.empty.model(mt)) glm.fit.null else >glm.fit)(x = X, y = Y, > >What am I doing wrong?Perhaps there's a 0 count in COUNT (which doesn't explain a crash but would explain lack of convergence). I hope that this helps, John ____________________________ John Fox Department of Sociology McMaster University email: jfox at mcmaster.ca web: http://www.socsci.mcmaster.ca/jfox