Thank's a lot for your help Ben. I already posted my question on r-sig-mixed-models! However you already answered what I needed to know.
2012/3/27 Ben Bolker <bbol...@gmail.com> > Lívia Dorneles Audino <livia.audino <at> gmail.com> writes: > > > > > I'm trying to make a glmm to identify the relationship between insect > > species richness with fragment size, isolation and time (different > years). > > I already tried to analyse it using poisson distribution error, but I > > always face with the following warning: > > *glm.fit: fitted probabilities numerically 0 or 1 occurred * > > > > This is probably hapenning because my dataset has a lot of zeros. So, > what > > error distribution should I use? > > > > I know you haven't gotten a lot of help on r-sig-mixed-models (sorry), > but it would probably be better to post this question there. The answer > is that this is a warning, not an error, so it indicates a need for > caution but not necessarily that anything is wrong. In this case, > an internal call to glm.fit() has difficulty when it tries to fit > a subset of that data that are all-zero or all-one. It's quite possibly > OK, provided that you've looked at your results, plotted predicted values, > etc., and everything seems to make sense. > > ______________________________________________ > R-help@r-project.org 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. > -- *Lívia Dorneles Audino* Doutoranda em Entomologia Laboratório de Ecologia e Conservação de Invertebrados Universidade Federal de Lavras [[alternative HTML version deleted]]
______________________________________________ R-help@r-project.org 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.
