On Mon, 4 Jan 2010 13:17:25 -0500, Fromm, Stephen (NIH/NIMH) [C]
<[log in to unmask]> wrote:
>As far as I know, there _is_ no difference between doing it that way and
doing it as an ANOVA, as long as you're only interested in the interaction term.
Adding, there's no difference in the case you use "partitioned error". There's
probably a difference if you use "pooled error" (see Henson and Penny).
>
>Stephen J. Fromm, PhD
>Contractor, NIMH/MAP
>(301) 451--9265
>________________________________________
>From: Vaidya, Jatin G [[log in to unmask]]
>Sent: Monday, January 04, 2010 10:38 AM
>To: Fromm, Stephen (NIH/NIMH) [C]; [log in to unmask]
>Subject: RE: 2 x 2 ANOVA
>
>Thanks! I know I can run this as a between group t-test after doing the
>subtraction but I'd like to know how to do it as an ANOVA.
>
>The link you sent was helpful. I'm curious if there is any other
>information available on how to actually implement this in SPM (more of
>an applied example).
>
>Thanks for your help.
>
>Jatin
>
>-----Original Message-----
>From: Stephen J. Fromm [mailto:[log in to unmask]]
>Sent: Friday, January 01, 2010 7:53 AM
>To: [log in to unmask]; Vaidya, Jatin G
>Subject: Re: 2 x 2 ANOVA
>
>On Thu, 31 Dec 2009 22:38:19 +0000, Jatin Vaidya <jatin-
>[log in to unmask]> wrote:
>
>>Hi,
>>
>>I'm trying to run a 2 X 2 design with PET data. The first factor is
>group
>(user
>>vs. control). The second factor is task (tapping vs. control); thus,
>this is a
>>repeated measures variable.
>>
>>I can't seem to determine how to run the analysis in SPM with this type
>of
>>dataset. Is there a good resource available for this?
>
>http://www.fil.ion.ucl.ac.uk/~wpenny/publications/rik_anova.pdf
>
>In this particular case, if you're only interested in comparing tapping
>with
>control (i.e., not interested in tapping alone or control alone or their
>average,
>but only their difference), you could also just subtract control from
>tapping at
>the subject level (or using ImCalc), and bring the difference to the
>group
>level, resulting in a 1-way, between-subjects ANOVA with no repeated
>measures.
>
>>
>>Thanks,
>>
>>Jatin
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