[R-lang] Re: anova formula repeated measures

[Ingo Plag]

Dear Michael,

the best way to do this might be using 
mixed effects regression.
This circumvents your problem and at the 
same time is a statistical technique 
that is superior to by-items and 
by-subjects anovas.

In case you are not familiar with it, 
Baayen's book (2008, Analyszing 
Linguistic Data, CUP) gives a nice 
introduction in one of the last chapters.

With best wishes,
Ingo Plag

> all
> 
> I am stuck on how to express a simple design for aov().
> 
> It's an experiment with two within-subjects factors (phonological
> properties of my stimuli) and one between-subjects factor (presentation
> mode: some subjects get things visually, some auditorily). There are
> multiple subjects of course, and multiple items in each factor and
> intersection.
> 
> If I left out the between-subjects factor, this is the normal way I would
> do this:
> 
> by items: aov(response ~ within1 * within2 + Error(item))
> 
> by subjects: aov(response ~ within1 * within2 + Error(subject/(within1 *
> within2)))
> 
> When I add in the between-subjects factor, I can't get the error term
> right:
> 
> by items: aov(response ~ within1 * within2 * between + Error(???))
> 
> by subjects: aov(response ~ within1 * within2 * between + Error(???))
> 
> I would have thought Error(item/between) and Error(subject/(within1 *
> within2)) respectively, but this does not work.
> 
> I've been searching the web and have not found any examples of this sort
> of mixed design with aov().
> 
> Does anybody have any ideas?
> 
> Mike H.
> 

-- 
Prof. Dr. Ingo Plag
English Linguistics
Fachbereich 3
Universitaet Siegen
Adolf-Reichwein-Str. 2
D-57068 Siegen

http://www.uni-siegen.de/~engspra/
tel. +49-(0)271-740-2560
tel. +49-(0)271-740-2349 (secretary)
fax tel. +49-(0)271-740-3246
e-mail: plag@anglistik.uni-siegen.de