entropy_j {treestats}

Intensive quadratic entropy statistic J.

Description

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.

Usage

entropy_j(phy)

Arguments

phy

phylo object or ltable

Value

intensive quadratic entropy statistic J

References

Izsák, János, and Laszlo Papp. "A link between ecological diversity indices and measures of biodiversity." Ecological Modelling 130.1-3 (2000): 151-156.