Dear SPM experts,
I have three different kinds of datasets recorded from 64 channels with 199 datapoints. I want to repeat each of dataset for 20 times (overall 60) and concatenate them to have 60 trials like:
Data (timepoint, channels, 1:3:60) = data1
Data (timepoint, channel, 2:3:60) = data2
Data (timepoint, channels, 3:3:60) = data3
I am going to estimate connectivity modulation by DCM between these three datasets.
1) If I define condition as like as:
D = conditions(D, 1:3:Ntrials, 'Condition 1')
D = conditions(D, 2:3:Ntrials, 'Condition 2')
D = conditions(D, 3:3:Ntrials, 'Condition 3')
I obtain different result with another definition of condition like :
D = conditions(D, 1, 'Condition 1')
D = conditions(D, 2, 'Condition 2')
D = conditions(D, 3, 'Condition 3')
Why DCM gives differen B matrix for the two labelling? I suppose to have same results from those two labelling since if DCM estimate connectivity by averaging of same trials, averaging of 20 same signals is as same as one signal.
Thank you for any response,
Pari
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