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Dear Frederik,

Why don't you just correlate your effect magnitudes across subjects with
the parameter values obtained by doing a BMA of all models within subject?
This sounds like a more standard strategy.

Best,

Vladimir

On Tue, Dec 1, 2015 at 12:40 PM, Frederik Van de Steen <
[log in to unmask]> wrote:

> Dear DCM experts,
>
> I am conducting a DCM study for ERP's . More specifically, one of the
> things i would like to do is to link DCM (modulatory) parameters with two
> temporal (early and late effect) ERP effects. I already fitted a quite
> large model space (400 models). My idea of linking parameter to these two
> effects was to calculate a mean (across subject) predicted effect
> (channels) for every fitted model for both temporal effects. Then, for each
> temporal effect, i would take 10% (or 50%) of the models with the smallest
> predicted effect and 10% of the models with the largest predicted effect
> (sort of 'data' driven post hoc family partitioning). Than i would use BMA
> for these models with lowest and highest effect. After I would simple use
> classical paired t-tests on these BMA parameters to see which parameters
> are significantly different.
>
> Is this a valid analysis strategy? I would be grateful for comments/advice
> regarding this issue.
>
> Kind regards,
>
> Frederik Van de Steen
>