Question about 3dTcorrMap

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1

Hi

I have a question about 3dTcorrMap
I tried to run the following commands:
3dTcorrMap -input brain+tlrc -CorrMap test1
3dTcorrMap -input brain+tlrc -seed brain+tlrc -CorrMap test2

I think I should get the same output for test1 and test2. However, the values in test2 were much smaller than test1. can anyone tell me what I miss here?

More for option -CorrMask, I cannot get the sub brick labels for the output file and I need to use -prefix to get -CorrMask output work. is that normal?

thanks,

Sue

2

Hi Sue,

I have not used 3dTcorrMap much, however the help suggests
that in the test1 case, there are some preprocessing steps
done before computing results.

Looking at the code and help, it seems like perhaps the only
preprocessing that is done by default is linear detrending.
So to get the same results for test1 and test2, consider
detrendinging first. Not detrending the -seed dataset could
seriously affect correlations with the detrended -input.

  • rick