comparing groups of different sizes

[Eric Maris]

Hi Andrew,





> I would like to compare a clinical group with a control group in one
condition using

> the cluster-

> based permuation test to see if there are significant differences between
the groups.

>

> I tried the following design matrix acting as if the control and clinical
group were

> two conditions,

> but get the error that the matrix is improperly specified:

>

> adhd=5;

> control=6;

>

> design=zeros(2,adhd+control);

>

> for i=1:adhd

>     design(1,i)=i;

> end

> for i=1:control

>     design(1,adhd+i)=i;

> end



Try this:



for i=1:control

    design(1,adhd+i)=i+adhd;

end



Or, even simpler:



design(1,:)=[1:(adhd+control)];





Good luck,



Eric Maris





dr. Eric Maris

NICI/Biological Psychology and

F.C. Donders Center for Cognitive NeuroImaging

University of Nijmegen

P.O. Box 9104

6500 HE Nijmegen

The Netherlands

T:+31 24 3612651 (NICI)

T:+31 24 3610754 (FCDC)

F:+31 24 3616066 (NICI)

E: maris at nici.ru.nl

MSc Cognitive Neuroscience : <http://www.ru.nl/master/cns/>
www.ru.nl/master/cns/









>

> design(2,1:adhd)=1;

> design(2,adhd+1:2*adhd+1) = 2;

>

> cfg.design   = design;

> cfg.uvar  = 1;

> cfg.ivar  = 2;

>

> [stat_controlvsadhd] = timelockstatistics(cfg,

> grandavgadhdnoise,grandavgcontrolnoise);

>

> Do you have any suggestions?

>

> Thank you

> Andrew

>

> ----------------------------------

> The aim of this list is to facilitate the discussion between users of the
FieldTrip

> toolbox, to share experiences and to discuss new ideas for MEG and EEG
analysis.

> See also http://listserv.surfnet.nl/archives/fieldtrip.html and

> http://www.ru.nl/fcdonders/fieldtrip.


----------------------------------
The aim of this list is to facilitate the discussion between users of the FieldTrip  toolbox, to share experiences and to discuss new ideas for MEG and EEG analysis. See also http://listserv.surfnet.nl/archives/fieldtrip.html and http://www.ru.nl/fcdonders/fieldtrip.
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