Hi all,

This is partly a statistical question as well as a question about R, but I am 
stumped!

I have count data from various sites across years. (Not all of the sites in the 
study appear in all years). Each site has its own habitat score "habitat" that 
remains constant across all years.

I want to know if counts declined faster on sites with high "habitat" scores.

I can construct a model that tests for the effect of habitat as a main effect, 
controlling for year

model1<-lmer(count~habitat+yr+(1|site), family=quasibinomial,data=m)
model2<-lmer(count~yr+(1|site), family=quasibinomial,data=m)
anova(model1,model2)

, but how do I test the interaction?

Thanks in advance,

Simon.





Dr. Simon Pickett
Research Ecologist
Land Use Department
Terrestrial Unit
British Trust for Ornithology
The Nunnery
Thetford
Norfolk
IP242PU
01842750050

        [[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.

Reply via email to