Dear Martin,
Martin Kronbichler wrote:
> Dear Dr.Penny,
>
> I didn't receive an answer to the question below,
> which i posted to the SPM Mailing List a week ago.
> Because, i think you programmed the Factorial Design
> Functions in SPM5, i hope you don't mind, that I'm sending
> this question to you directly
>
>
> "i just don't seem to able to set up a 2nd level ANOVA repeated measures
> design in SPM5 as i could in SPM2. Which option under Basic Models do i
> have to
> select to specify a factorial design with within subject factors?
You could use either (a) `Full Factorial' or (b) `Flexible Factorial'.
They will do the same thing but allow you to specify the design in a
different way (a) by assigned scans to cells (b) by entering scans eg.
subject by subject.
Sometimes (a) will be more efficient. Sometimes (b). Hopefully, by
looking at relevant examples in the SPM5 Manual
http://www.fil.ion.ucl.ac.uk/spm/doc/manual.pdf
eg. chapter 30 (2nd level fMRI examples), chapter 31 (PET examples)
you should be to figure out what's best for you.
> And is ist possible (and how) to specify a 2nd level design with within
> and between subject factors?"
>
It is. The only difference here is that for a within-subject
factor you may wish to consider the data as dependent. So when specifying
that factor you can select Independence->[NO].
**A note of caution**. There is currently a bug in SPM5 when specifying
nonsphericity for 2 or 3 way ANOVAs. We are working on a fix.
Best,
Will.
> Thanks and Greetings from Salzburg,
>
> Martin
>
>
> Martin Kronbichler, M.Sc.
> ---------------------------------------------
> Department of Neurology
> Center for Neurocognitive Research Christian-Doppler Clinic, Paracelsus
> Private Medical University
> Ignaz Harrerstr.79, A 5020 Salzburg, Austria
> e-mail:[log in to unmask]
> Tel.:+43/(0)/662/4483-3966
> ---------------------------------------------
> Department of
> Psychology
> Center for Neurocognitive Research University
> of Salzburg
> Hellbrunnerstr.34, A 5020 Salzburg, Austria
> e-mail:[log in to unmask]
> Tel.:+43/(0)/662/8044-5162
> Fax:+43/(0)/662/8044-5126
> ---------------------------------------------
>
>
>
--
William D. Penny
Wellcome Department of Imaging Neuroscience
University College London
12 Queen Square
London WC1N 3BG
Tel: 020 7833 7475
FAX: 020 7813 1420
Email: [log in to unmask]
URL: http://www.fil.ion.ucl.ac.uk/~wpenny/
|