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arXiv · 1705.10548

A Faster Construction of Greedy Consensus Trees

Paweł Gawrychowski·Gad M. Landau·Wing-Kin Sung·Oren Weimann
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Abstract

A consensus tree is a phylogenetic tree that captures the similarity between a set of conflicting phylogenetic trees. The problem of computing a consensus tree is a major step in phylogenetic tree reconstruction. It also finds applications in predicting a species tree from a set of gene trees. This paper focuses on two of the most well-known and widely used oconsensus tree methods: the greedy consensus tree and the frequency difference consensus tree. Given $k$ conflicting trees each with $n$ leaves, the previous fastest algorithms for these problems were $O(k n^2)$ for the greedy consensus tree [J. ACM 2016] and $\tilde O(\min \{ k n^2, k^2n\})$ for the frequency difference consensus tree [ACM TCBB 2016]. We improve these running times to $\tilde O(k n^{1.5})$ and $\tilde O(k n)$ respectively.

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Paweł Gawrychowski, Gad M. Landau, Wing-Kin Sung, Oren Weimann. 2017-05-30. A Faster Construction of Greedy Consensus Trees. https://arxiv.org/abs/1705.10548

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