Dear All,

In this post

http://www.nitrc.org/forum/message.php?m...

Alfonso wrote that "ICC is sign-independent (since it considers r-squared values), while global correlation is not (it averages the actual r correlation-coefficient values, considering their sign, so positive and negative correlations will cancel out)".

I`m interested in using global correlation and had a look at the formula (please see attachment) provided in the paper "Conn: a functional connectivity toolbox for correlated and anticorrelated brain networks". Now I`m confused. Doesn`t this formula use absolute values which would mean that positive and negative values are aggregated and not canceled out?

Thank you very much in advance