Hello, I am analysing counts data with a mixed model using lmer procedure. I therefore use the quasipoisson distribution but I'm not sure if this is sufficient to account for overdispersion. Actually the results are not very different to what I get when specifying a poisson distribution although my data are clearly overdispersed.
this my model: >model <- lmer(NB ~ T + volume + (G|col) , data=immuno15, >family=quasipoisson) where - NB is bacterial count in haemolymph of ants 10h after bacteria injection(measure of immunocompetence) - T is the treatment applied to ants - volume is the volume of haemolymph sample from ants - col is the colony of origin of ants, which is a random factor I know it's possible to get a estimator of overdispersion with: >sum.model <- summary(model) >[EMAIL PROTECTED] but I don't know how to interpret this scale parameter. Does anyone could help me? thanks a lot, Aurelie Bocher _________________________________________________________________ mobile comme sur PC ! http://mobile.live.fr/messenger/bouygues/ ______________________________________________ [email protected] 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.
