Dear Peter (and all other DCM-experts),
basically I wonder what the (conceptual) difference is between
calculating a contrast of connections in DCM (fixed effects) via the GUI
("Dynamic Causal Modelling" -> "review" -> "contrast of connections")
and calculating the same contrast using "spm_dcm_sessions.m".
In my specific case the input to the first (GUI) approach was a Bayesian
parameter average (BPA) of 32 single-subject DCMs using
spm_dcm_average.m, whereas the same 32 single-subject models served as
input to the second (spm_dcm_sessions.m) approach.
Results for the GUI are:
Mean: 2.1267
Variance: 8.6268e-05
Posterior probability: ~100 %
Results using spm_dcm_sessions:
Mean: 0.5131
Variance: 0.0528
Posterior probability: 98.7 %
Thanks a lot for any clarifications,
Thilo
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Thilo Kellermann
Department of Psychiatry, Psychotherapy and Psychosomatics
Uniklinik RWTH Aachen
JARA Translational Brain Medicine
Pauwelsstr. 30
52074 Aachen
Germany
Tel.: +49 (0)241 / 8089977
Fax.: +49 (0)241 / 8082401
E-Mail: [log in to unmask]
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