help > RE: ANCOVA rank deficient
Dec 7, 2017  01:12 AM | Juan Pablo Princich - Neurociencias Hospital El Cruce, Buenos Aires
RE: ANCOVA rank deficient
Dear Andrew, 

I used NBS to compare 2 groups as stated in this post accounting for age and sex differences using a t-test, with a [0 1 0 0] contrast type as you suggest.
I found one component with 6 connection pairs that shall have higher connectivity in patients than in controls as the matrices were arranged in the same way as mentioned in this post (patients first followed by controls).

But i get confused interpreting results because when i extract the identified connections for all participants and perform individual tests (mann withney, non parametric)  on each connection pair between patients and controls , the values on patients are indeed significantly lower than in controls... contrary to the NBS results.


Will really appreciate your comments and possible explanations for this ambiguity.  Please be aware that age and sex effects are not regressed out for the individual connections test, but significance levels ares still very low (p.001).


Sincerely 
Juan P

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TitleAuthorDate
Giulia Forcellini May 11, 2016
Andrew Zalesky May 12, 2016
RE: ANCOVA rank deficient
Juan Pablo Princich Dec 7, 2017
Andrew Zalesky Dec 7, 2017
Juan Pablo Princich Dec 13, 2017
Juan Pablo Princich Dec 18, 2017
Juan Pablo Princich Aug 20, 2016
Andrew Zalesky Aug 22, 2016