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arXiv · 1704.08680

An Improved Integrality Gap for Steiner Tree

Ali Çivril·Muhammed Mirza Biçer·Berkay Tahsin Tunca·Muhammet Yasin Kangal
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Abstract

A promising approach for obtaining improved approximation algorithms for Steiner tree is to use the bidirected cut relaxation (BCR). The integrality gap of this relaxation is at least $36/31$, and it has long been conjectured that its true value is very close to this lower bound. However, the best upper bound for general graphs was an almost trivial $2$. We improve this bound to $3/2$ by a combinatorial algorithm based on the primal-dual schema.

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Ali Çivril, Muhammed Mirza Biçer, Berkay Tahsin Tunca, Muhammet Yasin Kangal. 2017-04-27. An Improved Integrality Gap for Steiner Tree. https://arxiv.org/abs/1704.08680

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