The intensive quadratic entropy statistic J is given by the average distance between two randomly chosen species, thus given by the sum of all pairwise distances, divided by S^2, where S is the number of tips of the tree.
The intensive quadratic entropy statistic J is given by the average distance between two randomly chosen species, thus given by the sum of all pairwise distances, divided by S^2, where S is the number of tips of the tree.