Hi Marko,
Thanks for forwarding this --
Tom Nichols:
>> So, for the record, FDR makes no assumptions about the topology of
>> the search region. Chop-chop-chop away. As long as the image used
>> to determine your search region is orthogonal/independent from the
>> experimential signal of interest (as the voxel grand means surely are),
>> your fine.
-- It's a good point, but it's specific to FDR; FWE/RF correction does
take account the size of the search region, and with SVC it takes
account of the shape (as Christophe said).
This is perhaps another motivation for using FDR in preference to FWE,
as discussed in this thread:
http://www.jiscmail.ac.uk/cgi-bin/webadmin?A2=ind0612&L=SPM&P=R44839
But I'm still interested to know whether people think SVC is a good
idea for FWE of tightly masked data (functional or structural)...
Also, Tom's other comment is interesting --
>> Let me know if the brain volume truncation helps. I had some
>> students try it here and it didn't make that much of a difference.
-- I'd wondered about FDR's behaviour in response to different search
volume sizes, but it sounds like it's not too critical, which is
useful to know.
Cheers,
Ged.
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