Dear all, I've read numerous posts about the random and nested factors in lme, comparison to proc Mixed in SAS, and so on, but I'm still a bit confused by the notations. More specifically, say we have a model with a fixed effect F, a random effect R and another one N which is nested in R.
Say the model is described by Y~F Can anyone clarify the difference between : random = ~1|R:N random = ~1|R/N random = ~R:N random = ~R/N random = ~R|N random = ~1|R+N or direct me to an overview regarding notation of these formulas in lme (package nlme)? The help files weren't exactly clear to me on this subject. What confuses me most, is the use of the intercept in the random factor. Does this mean the intercept is seen as random, has a random component or is it just notation? In different mails from this list I found different explanations. Thank you in advance. Cheers Joris -- Joris Meys Statistical Consultant Ghent University Faculty of Bioscience Engineering Department of Applied mathematics, biometrics and process control Coupure Links 653 B-9000 Gent tel : +32 9 264 59 87 joris.m...@ugent.be ------------------------------- Disclaimer : http://helpdesk.ugent.be/e-maildisclaimer.php [[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.