Welcome to TREE BALANCE
Tree balance plays an important role in phylogenetics and other research areas, which is why several indices to measure tree balance or imbalance have been introduced over the years. However, the great variety of available indices sometimes makes it hard to decide which index to use.
This website presents results on tree (im)balance indices that make comparing them significantly easier. It is based on the book “Tree Balance Indices – A Comprehensive Survey” by Fischer, Herbst, Kersting, Kühn, and Wicke (2023), Springer, ISBN: 978-3-031-39799-8.
The aim of this website is to summarize up-to-date information on all known such indices. In case you want to contribute some new information, please send us an e-mail: treebalanceindices@gmail.com
Imbalance Indices
Imbalance indices measure the degree of imbalance of a tree. Their values thus increase with increasing imbalance of the tree, leaving the maximum to the caterpillar tree and the minimum, in case the leaf number equals a power of two, to the fully balanced tree. The most famous imbalance indices are the Sackin, Colless and total cophenetic indices.
Balance Indices
Balance indices measure the degree of balance of a tree. Thus, their values increase with increasing balance of the tree, leaving the minimum to the caterpillar tree and the maximum to the fully balanced tree (provided that the leaf number is a power of two). The most famous members of this class of indices are the B1 and B2 indices.
TREE BALANCE 