Print

Print


Hi Mona,

Almost.  An appropriate model for you to follow on the details page is the
one-factor 4-levels repeated measures, as your effects  repeat in each
subject.  You'll need 3 evs modelling your two factors and interaction
rather than the evs modelling single 4-level factor.  Your current design
should be almost the same (I think), but won't quite get the degrees of
freedom right for the ANOVA stats.

Hope that helps,

Eugene

--

Centre for Functional MRI of the Brain (FMRIB) | University of Oxford
John Radcliffe Hospital | Headington
OX3 9DU | Oxford | UK

Ph: +44 (0) 1865 222 523 | Mob: +44 (0) 7946 362 059 | Fax: +44 (0) 1865 222
717

--


On 2 September 2010 13:57, Mona Maneshi <[log in to unmask]> wrote:

> I am resending this email, since I did not hear from you.
>
>
> Hello FSL experts,
>
> I have a question regarding the higher level analysis using FEAT. I have a
> repeated 2-factor 2-level ANOVA design. I have already read your web page on
> FEAT details: "ANOVA: 2-factors 2-levels (Random effects)", but I could not
> find my answer there.
> Each subject in my study has 4 different runs (1 run in each of 2-level
> TIME factor, and each of 2-level LEARNING factor). I am interested in the
> main effect of LEARNING factor. Since I have 4 runs for each subject, I
> thought that to increase the power of analysis, maybe it is better to run a
> Fixed-effects analysis for each subject first (I have attached design.ppm
> file), and then to combine COPE of LEARNING factor contrast (C1), which I am
> interested in, for different subjects using mixed effect model (e.g. FLAME1)
> with a simple averaging as EV. Also I can run the same mixed-effect model to
> find the average of Time factor (C2) and Interaction (C2) between subjects.
> Would you please let me know whether this method is correct?
>
> Thanks in advance,
> Mona
>