Message-ID: <loom.20090207T163104-883@post.gmane.org>
Date: 2009-02-07T16:34:56Z
From: Dieter Menne
Subject: lme() direction
Mike Lawrence <mike <at> thatmike.com> writes:
>
>Would it improve things if "type" were a continuous variable rather
>than categorical? I chose words at the extreme ends of a valence
>rating scale but I still have the raw valence ratings for each word.
>
> >
> > With the interaction, the extreme would be
> > summary(lme(rt~type*color*word, data=a,random=~1|id))
> >
> > or, less extreme
> >
> > summary(lme(rt~type*color+color:word, data=a,random=~1|id))
..
Something like
summary(lme(rt~type*color+color:as.numeric(word), data=a,random=~1|id))
(please replace as.numeric() by the raw valence, the example above it
simply wrong)
could gain you a few degrees of freedom if you are willing to accept the
linear hypothesis. And as there is something like raw valence, one should
not throw away details about a-priori ordering in favor of a categorical
hypothesis.
Dieter