Dear expeRts,

I am facing some problems with lme with 3 fixed within-subjects 
factors (S, R, T) to be followed up by a post-hoc test.

Each of the 3 factors can be 0 or 1 (in fact, all 3 could be 0, so 
there are 8 conditions).

I know how to do this with an 8-level condition factor:

require(nlme)         ## for lme()
require(multcomp)     ## for multiple comparison stuff
RT.aov <- aov(RT ~ Condition + Error(Subject/Condition), Data)
RT.lme <- lme(RT ~ Condition, random = ~1 | Subject/Condition, Data)
summary(glht(RT.lme, linfct=mcp(Condition="Tukey")))

but I am unable to get lme to work with 3 factors despite trying to 
use some hints provided in the archives.

The lme solution should be equivalent to:

RT.aov <- aov(RT ~ S*R*T + Error(Subject / (S*R*T)), Data)

and then I want to do:

RT.lme <- lme(RT ~ S*R*T ---THE GAP---)

summary(glht(RT.lme, linfct=mcp(? S*R*T ? = "Tukey")))


These didn't work:

RT.lme <- lme(RT ~ S*R*T, random = ~1 | Subj/(S*R*T), WMU2C)
#Error in getGroups.data.frame(dataMix, groups) :  Invalid formula for groups

RT.lme <- lme(RT ~ S*R*T, random = ~1 | (Subj + (S %in% Subj) + (R 
%in% Subj) + (T %in% Subj)), WMU2C)
#Error in sprintf(gettext(fmt, domain = domain), ...) :  object 
"form" not found

RT.lme <- lme(RT ~ S*R*T, random = ~S*R*T|Subj, WMU2C)
#R stalls


and I couldn't make use of this suggestion - R complains about 
unexpected characters and I to be honest I don't understand what it 
is supposed to do anyway:

 > lme((y~fact1*fact2,
+ random=list(subj=pdIdent(form=~fact1-1),
+ subj=~1,
+ fact2=~1),


Thanks very much for your help!

Ulli

Ullrich Ecker
Cognitive Science Laboratories
University of Western Australia

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