You are confused. You have not specified a "grouping" random effect, so this is not a mixed effect model as it stands.
If this is a homework problem, ask a teacher or classmate for help. Otherwise, try consulting your local statistician. You do not appear to understand the concepts of mixed effects models, so just walking you through a lme model specification is not likely to help. Bert Gunter On Tue, Jul 27, 2010 at 8:24 PM, Murat Tasan <mmu...@gmail.com> wrote: > hi all - i'm having trouble using lme to specify a mixed effects > model. > i'm pretty sure this is quite easy for the experienced anova-er, which > i unfortunately am not. > > i have a data frame with the following columns: > col 1 : "Score1" (this is a continuous numeric measure between 0 and > 1) > col 2 : "Score2" (another continuous numeric measure, this time > bounded between 0 and 100) > col 3 : "Class" (a fixed-effects factor with 4 (ordered) levels) > > i have ~2000 observations, but unbalanced w.r.t. the "Class" factor. > each observation has a distinct "Score1" and "Score2". > > i'd like to try a mixed-effect anova model where "Score1" is the > dependent response, and "Score2" and "Class" are the explanatory > covariates (with an expected interaction between them). > > naively, i simply tried: > aov(Score1 ~ Score2 * Class) > > but i'm pretty sure this treated "Score2" as a fixed-effects covariate > with a single observation per level. > > can anyone help guide me to the correct model specification using > lme(...)? > > thanks much for any help! > > ______________________________________________ > 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. > ______________________________________________ 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.