Dear Ian,
Yes, absolutely, this is easily possible. What you have to do is to specify a single base model which you can then subsequently use to create all the different model variants you are interested in. For this purpose, you can write a little Matlab script that loads the base model, changes the matrices for the modulatory inputs (DCM.b) and the matrix for the driving inputs (DCM.c), and saves the new DCM. Finally, after you have created these different models, you can use the function spm_dcm_estimate to fit each model.
All the best,
Klaas
Von: Ian Ballard <[log in to unmask]>
An: [log in to unmask]
Gesendet: Dienstag, den 23. Juni 2009, 18:59:07 Uhr
Betreff: [SPM] DCM- manual entry
Hello,
I am working on a DCM analysis of fMRI data and I have a large number of models (~100) that I want to test. Each of the models has the same structure, but I vary the location of the driving input and which pathways have bilinear effects. It seems that it would be much easier and faster to enter matrices specifying the bilinear connections in matlab than to manually specify them through the GUI. Is this possible? If so, do you have any suggestions on how to do this (I usually use the SPM GUI).
Thanks,
Ian
