Why would a negative correlation be difficult to interpret? It just
means that when one variable's value is high, the other's tends to be low.
±θΑφΗφ wrote:
> Dear experts
> I'm analysing seed-based (hippocampus) resting-state functional
> connectivity between patient and control groups by using spm8 and
> especially REST program (http://restfmri.net/forum/?q=rest)
> The resulting zFC maps of include both positive and negative
> correlations.
> However, negative correlation (or anti-correlation) seems pretty
> difficult to interpret the results, and moreover, increased negative
> correlation in patient groups results in significant positive clusters
> in 'control_to_patient' 2nd-level analysis using two-sample t-test,
> which makes me more confusing.
> Therefore, I wish to remove negative correlation maps from the zFC
> files and just want to compare positive correlation maps between the
> groups (and I found some articles used this methods).
> How can I do this?
> Any hints would be appreciated.
> Thanks in advance for your kindness.
> Kim
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