Marianne Stephan <mariannestephan <at> hotmail.com> writes: > Dear R and statistics experts: > > I have data of a behavioral experiment with the aim to > investigate the effect of a memory task on motor > learning. > > Question: > I would appreciate help in figuring out a > possible formula to determine whether motor learning across > sessions differs between 2 groups. > > Design: > - 2 Groups: group A: n=10 subjects, group B: n=10 > - 6 motor learning sessions: baseline; immediately after > memory task; 6h, 24h, 30d later, and 30d later > with a different motor task > - dependent variable: response time (RT) > > I tried the following: > (lme4 package of R, I assumed that > Subject is the random factor, and Session and Group the fixed factors.) > > fm1 <- lmer(RT ~ Session + Group + (1|Subject) + (1|Subject:Session), table) > > I would appreciate any help on the formula or the > choice of statistical approach.
Please re-post to the r-sig-mixed-mod...@r-project.org list. Your basic approach looks reasonable; you should be able to use (1|Subject/Session) [check whether the results are identical] for this nested analysis. May provide more comments in the other forum. Ben Bolker ______________________________________________ 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.
