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help > RE: Threshold on the connectivity matrix
Sep 2, 2013 09:09 PM | Andrew Zalesky
RE: Threshold on the connectivity matrix
Dear David,
Applying a threshold to remove spurious connections may be useful. To omit a connection from consideration in statistical testing when using the NBS simply set that connection to zero in every connectivity matrix. Any connection with a value of zero for every subject will be automatically excluded from statistical testing.
I hope that helps.
Andrew
Originally posted by David Coynel:
Applying a threshold to remove spurious connections may be useful. To omit a connection from consideration in statistical testing when using the NBS simply set that connection to zero in every connectivity matrix. Any connection with a value of zero for every subject will be automatically excluded from statistical testing.
I hope that helps.
Andrew
Originally posted by David Coynel:
Hi, and thanks for this nice toolbox.
I'm working with tractography data from FSL's probtrackx. I usually apply a low threshold to get rid of spurious connections, based on the group-average connectivity matrix.
In the paper describing NBS, you propose to work directly with raw data in order to avoid systematic sparsity differences. In my case, some NBS networks could get significant even though they mainly consist of connections that I would normally not consider, as they are quite unlikely to be true.
What strategy would you advice ?
Thanks,
David
I'm working with tractography data from FSL's probtrackx. I usually apply a low threshold to get rid of spurious connections, based on the group-average connectivity matrix.
In the paper describing NBS, you propose to work directly with raw data in order to avoid systematic sparsity differences. In my case, some NBS networks could get significant even though they mainly consist of connections that I would normally not consider, as they are quite unlikely to be true.
What strategy would you advice ?
Thanks,
David
Threaded View
| Title | Author | Date |
|---|---|---|
| David Coynel | Sep 2, 2013 | |
| Andrew Zalesky | Sep 2, 2013 | |
| David Coynel | Sep 3, 2013 | |