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arXiv · 1902.03321

Exchangeable and Sampling Consistent Distributions on Rooted Binary Trees

Ben Hollering·Seth Sullivant
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Abstract

We introduce a notion of finite sampling consistency for phylogenetic trees and show that the set of finitely sampling consistent and exchangeable distributions on n leaf phylogenetic trees is a polytope. We use this polytope to show that the set of all exchangeable and infinite sampling consistent distributions on 4 leaf phylogenetic trees is exactly Aldous' beta-splitting model and give a description of some of the vertices for the polytope of distributions on 5 leaves. We also introduce a new semialgebraic set of exchangeable and sampling consistent models we call the multinomial model and use it to characterize the set of exchangeable and sampling consistent distributions.

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Ben Hollering, Seth Sullivant. 2019-02-08. Exchangeable and Sampling Consistent Distributions on Rooted Binary Trees. https://arxiv.org/abs/1902.03321

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