Dear Marko, Shari and others
>> [shari] Please look this up in the mailbase. This is not a highly
>> recommended method of multiple correction. Please read Karl and/or
>> Will's e-mail on the mail base. My suggestion, based on what I have
>> learn from will, is that you use FWE instead.
If you check the literature instead of the mailbase and see how many
people use FDR, and how many new methods are based on FDR, you may find
something totally different.
>> [will] As to what you *should* use, I can't say. Historically, the
>> advice has been
>> to always try for voxel-level FWE 0.05. But there are many papers out
>> these
>> days using FDR. As long as you adequately describe the approach
>> you've used and
>> what it means, you're on safe ground.
Historically, SPM has always used a modified FWE measure based on
smoothing. Many people who use FDR don't want to smooth their data to
bits to get results. Note that here, `getting results' is interpreted as
`surviving the p=0.05 threshold'.
As you can read in Will's e-mail, it is perfectly legal to report
results based on a p=0.08 threshold, as long as you accurately describe
what you're doing. Your next big problem then is getting your paper past
the reviewers...
Best wishes
Alle Meije
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