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On Thu, 30 Jun 2005 13:45:14 +0100, Christian Matthiae <[log in to unmask]> wrote: >Hi Elif, >i am not an expert, so i am not completely sure about this. >But i think there is no problem, as you dont get an error, but only a >warning. Every DCM matrix contains not specified connections, which can not >be estimated. During estimation these connections get the value Nan, which >is indicated by the displayed warning. So i think your estimation was >finished correctly. The reason that you get this warning after the first >step is, that iteration stops, if the changes from one step to the next are >smaller than a threshold (1e-6 i think). This condition is met in your >analysis after the first step (dp: 1.139079e-21). This is a little >astonishing for me, but perhaps could be due to a very simple model? >If i am wrong here one of the spm/dcm should please correct me. >Hope this helps, >Christian > > >On Thu, 30 Jun 2005 01:26:49 +0100, Elif Ozdemir <[log in to unmask] >HARVARD.EDU> wrote: > >>Dear all, >> >>I am conducting a DCM analysis on a dataset that we acquired from a subject >>using a sparse temporal sampling method (TR=15, TA=1.75 sc). I have defined >>three VOIs for two (out of four) conditions. When I do the estimation, I >>get the error message below after the first iteration. I have read the >>previous posts about this error and have the latest DCM updates. >> >>After getting the error message, I am still able review the results. The >>histogram is drawn only for B probabilities, not for B modulatory effects. >>In addition, even though the VOIs are circled, there are no numbers. >> >>I have replicated the results of the attention data from Dr.Penny's website >>without these error messages. >> >>Any ideas how to fix this? Any input/help is greatly appreciated! >>Thanks! >> >>Elif >> >>"E-Step(-): 1 F: -1.043264e+03 dp: 1.139079e-21 >>Warning: Returning NaN for out of range arguments >>> In /usr/local/spm2/spm_Ncdf.m at line 76 >> In /usr/local/spm2/spm_dcm_estimate.m at line 72 >> In /usr/local/spm2/spm_dcm_ui.m at line 312" Hi Christian, Thanks for the message. I have specified several DCMs with conditions ranging from two to 6, VOIs from 2 to 6 and intrinsic conditions from 2 to 12. None of them worked (at least completely). A and B probabilities are there. But no numbers on the regions. There are dashed lines instead of solid ones with red dots around the VOIs. In the last DCM model, I had 8 conditions in the design matrix, took two of those conditions to the DCM, had 6 VOIs and 12 intrinsic connections. For the condition one and two, I had same number of connections (I think 6). The NaN error message still comes up after the first iteration. Any ideas as to how I could make these dashed lines solid and see the corresponding numbers? Loading DCM.A mat gives me only -1s and 0s. Any help is very much appreciated!!! Elif