Dear DCM experts
I realize there are (at least) 2 ways for doing the DCM model comparison at
the group level, and I would like to ask what is the difference between them,
and in which conditions should each one be applied (for fMRI):
1- Do the Baysian model comparison at the individual level, multiply the BFs of
all individuals for each comparison to get GBF, and choose the model with the
largest GBF given that the PER is reasonalbe (??). (e.g. as in Stephan
Weiskopf et al. 2007).
2- Get the model evidence from DCM.F, and sum up this value across
individuals for each model. Choose the model with largest sum (suggested by
Stefan Kiebel in SNDS workshop (Dead Sea 2007), and based on Kiebel Garrido
et al. 2007).
I'd appreciate your advice
Tali Bitan
Haifa University, Israel
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