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arXiv · 1811.05916

A Duality Based 2-Approximation Algorithm for Maximum Agreement Forest

Neil Olver·Frans Schalekamp·Suzanne van der Ster·Leen Stougie·Anke van Zuylen
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Abstract

We give a 2-approximation algorithm for the Maximum Agreement Forest problem on two rooted binary trees. This NP-hard problem has been studied extensively in the past two decades, since it can be used to compute the rooted Subtree Prune-and-Regraft (rSPR) distance between two phylogenetic trees. Our algorithm is combinatorial and its running time is quadratic in the input size. To prove the approximation guarantee, we construct a feasible dual solution for a novel linear programming formulation. In addition, we show this linear program is stronger than previously known formulations, and we give a compact formulation, showing that it can be solved in polynomial time

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Neil Olver, Frans Schalekamp, Suzanne van der Ster, Leen Stougie, Anke van Zuylen. 2018-11-14. A Duality Based 2-Approximation Algorithm for Maximum Agreement Forest. https://arxiv.org/abs/1811.05916

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