A balance index for phylogenetic trees based on quartets
نویسندگان
چکیده
We define a new balance index for phylogenetic trees based on the symmetry of the evolutive history of every quartet of leaves. This index makes sense for polytomic trees and it can be computed in time linear in the number of leaves. We compute its maximum and minimum values for arbitrary and bifurcating trees, and we provide exact formulas for its expected value and variance for bifurcating trees under Ford’s α-model and Aldous’ β-model and for arbitrary trees under the α-γ-model.
منابع مشابه
Limit distribution of the quartet balance index for Aldous's b>=0-model
This note accompanies T. Mart́ınez–Coronado, A. Mir, F. Rosselló and G. Valiente’s work “A balance index for phylogenetic trees based on quartets”, introducing a new balance index for trees. We show here that this balance index, in the case of Aldous’s β ≥ 0–model, convergences weakly to a contraction–type distribution.
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تاریخ انتشار 2018