Bioequivalence and Bioavailability Forum

Hi all,

❝ random=~drug - 1|subj

I do not offer an answer to the question at all, only I wish to say that I have no ideas, generally, how syntactically R works for lme and lmer when specifying random effects.
All the stuff that involves "~", "|" for random effects is entirely obscure to me, and I tried to read the various online resources for it, and help files for packages. I even ordered the book by Pinheiro & Bates to learn from it, but that book assumes that the reader knows everything there is to about mixed models and R syntax before you open it on page 1. It is also not clear to me how covariance matrix structures are actually set using the R functions.

So, I think the question you asked jabriges is also highly relevant for me in a very general sense. I hope someone will chime in an educate me about the syntax.