[R] lme:correlationstructure AR1 and random factor

Dear helpers, I tried these models to run in the package nlme, but allways got the same error message... I have a correlation in 5 sessions within a field (n=12) with ten traps in one field. res2a <- lme(response~x+y+z+treatment),correlation = corARMA(form = ~ session|trapfield, p = 1, q = 0), r

[R] binary data with correlation

Dear posters, I have a question concerning binary data analysis. I have presence absence data of 5 sampling sessions within 3 years, of 12 fields. Each field had 12 traps. I would like to analyse the data with a Generalized Estimating Equations (GEE) Model in R. For the abundance data I used a gls