search for: t_cholmod_super_numeric

Hi, I am getting a warning message when I am fitting a generalized linear mixed model (m1.2 below). CHOLMOD warning: matrix not positive definite Error in objective(.par, ...) : Cholmod error `matrix not positive definite' at file:../Supernodal/t_cholmod_super_numeric.c, line 614 Any idea? Thanks for your help, Reza > sessionInfo() R version 2.4.1 (2006-12-18) i386-pc-mingw32 locale: LC_COLLATE=English_United States.1252;LC_CTYPE=English_United States.1252;LC_MONETARY=English_United States.1252;LC_NUMERIC=C;LC_TIME=English_United States.1252 attach...

...mer(aphids~totmas+zone+(1|zone/site), family=quasipoisson) Totmas is also a continuous variable just like densroot, but in this case I receive the following message: CHOLMOD warning: &߆e Error in objective(.par, ...) : Cholmod error `matrix not positive definite' at file:../Supernodal/t_cholmod_super_numeric.c, line 613 Moreover, if I test yet another continuous variable "vitality", to my surprise R just crashes completely. This is a mystery to me, especially because the variables totmas or vitality don't give any problem when I build the exact same models in SAS with proc glimmix......

...1|site/hab)) which also made R crashing. And, fm2<-lmer(data=NGud,family=poisson, seed~hab*seedtray +(1|site/hab)) and for this, I obtained : CHOLMOD warning: matrix not positive definite Error in devLaplace(PQLpars) : Cholmod error `matrix not positive definite' at file:../Supernodal/t_cholmod_super_numeric.c, line 614 J?r?me Lema?tre ?tudiant au doctorat Chaire de recherche industrielle CRSNG - Universit? Laval en sylviculture et faune & D?partement de biologie, Facult? des sciences et de g?nie Pavillon Alexandre-Vachon Universit? Laval Qu?bec, QC G1K 7P4 t?l : (418) 656-2131 poste 2917 Lo...

...IC of each model. For 1 of the models (the one in the [] above) I'm getting the following error message, which I don't know what it means: CHOLMOD warning: matrix not positive definite Error in objective(.par, ...) : Cholmod error `matrix not positive definite' at file:../Supernodal/t_cholmod_super_numeric.c, line 614 Could anybody give me some advice on using Tweedie distributions and does anybody have an idea what this error message means. Thanks a lot in advance, Cheers, Cristina.