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arXiv · 2404.16131

Combinatorial Approximations for Cluster Deletion: Simpler, Faster, and Better

Vicente Balmaseda·Ying Xu·Yixin Cao·Nate Veldt
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Abstract

Cluster deletion is an NP-hard graph clustering objective with applications in computational biology and social network analysis, where the goal is to delete a minimum number of edges to partition a graph into cliques. We first provide a tighter analysis of two previous approximation algorithms, improving their approximation guarantees from 4 to 3. Moreover, we show that both algorithms can be derandomized in a surprisingly simple way, by greedily taking a vertex of maximum degree in an auxiliary graph and forming a cluster around it. One of these algorithms relies on solving a linear program. Our final contribution is to design a new and purely combinatorial approach for doing so that is far more scalable in theory and practice.

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Vicente Balmaseda, Ying Xu, Yixin Cao, Nate Veldt. 2024-04-24. Combinatorial Approximations for Cluster Deletion: Simpler, Faster, and Better. https://arxiv.org/abs/2404.16131

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