Relative Betweenness

Hi all,

  I'm a bit confused about the calculation of the relative betweennness. As far as I see in the source code, the betweenness is normalized by (n-1)(n-2)/2 for directed and (n-1)(n-2) for undirected graphs:

--snip-- //GraphDistance.java
            if (!mDirected) {
                mBetweenness[s_index] /= 2;
            }
            if (this.mRelativeValues) {
                mCloseness[s_index] = 1.0 / mCloseness[s_index];
                mBetweenness[s_index] /= ((mN - 1) * (mN - 2)) / 2;
            }
--snap--

  However, this is not correct and should be directly opposed. The betweenness for directed graphs is normalized by (n-1)(n-2) and for undirected graphs by (n-1)(n-2)/2.

  Is there something I missed?

Thanks
  matthias