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I mean the former.

Vladimir

On Tue, Dec 1, 2015 at 1:32 PM, Frederik Van de Steen <
[log in to unmask]> wrote:

> Dear Vladimir,
>
> Thanks for you reply. I have an additional question. Do you mean
> correlating the observed effects with BMA parameters? Or predicted effects?
> If the later how can i get the predicted effect with BMA parameters?
>
> best
> Citeren Vladimir Litvak <[log in to unmask]>:
>
> 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
>>>
>>>
>
>
>