The area per pair index calculates the sum of the number of
edges on the path between all two leaves. Instead, the area per pair index
(APP) can also be derived from the Sackin (S) and total cophenetic index
(TC):
\( APP = \frac{2}{n}\cdot S - \frac{4}{n(n-1)}\cdot TC\)
\(APP = 2/n * S - 4/(n(n-1)) * TC\)
Usage
area_per_pair(phy, normalization = "none")
Arguments
- phy
phylo object or ltable
- normalization
"none" or "yule", in which case the acquired result
is divided by the expectation for the Yule model.
Value
Area per pair index
References
T. Araújo Lima, F. M. D. Marquitti, and M. A. M. de Aguiar.
Measuring Tree Balance with Normalized Tree Area. arXiv e-prints, art.
arXiv:2008.12867, 2020.