Dear all,
I am hoping someone can shed a light on what I observed with a data I have
been working on. It is a simple set of DTI-FA maps of old and young people
and I run TBSS on the data. The data is unbalanced, I have 36 olds and 18
youngs. After running randomize, p values (both corrected and uncorrected
p-images) are constant 0.99952 almost throughout the whole WM tracts. On the
other hand, t-statistics show variance across space, so they look normal.
Can anyone speculate why I am getting a fixed p value throughout the entire
WM tracts? Moreover, it is the same for both corrected and uncorrected.
I browsed through the email discussions but I could not find a similar issue.
Thanks in advance for any insights you might have.
best,
Tugan Muftuler
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