Hi - this default is fairly sensible - it says you want equal probability of false positives vs. false negatives (and is not directly comparable with a p<.05 null hypothesis test - that's a different animal).  For more details on the mixture modelling and alternative hypothesis testing see the various papers by Beckmann and by Woolrich listed on our publications page.

Cheers, Steve.



On 5 Aug 2010, at 14:41, William Sohn wrote:

Dear FSL community,

This is more of a statistical question but I was wondering what the alternative hypothesis test does?  When I run MELODIC on the default setting it says the p>.5.  I was wondering how to interpret it.  Should I be setting this to a much lower setting or is it fine to keep it as is.

Thank you,

-William Sohn



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