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arXiv · 1006.2249

Integrality Gap of the Hypergraphic Relaxation of Steiner Trees: a short proof of a 1.55 upper bound

Deeparnab Chakrabarty·Jochen Koenemann·David Pritchard
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Abstract

Recently Byrka, Grandoni, Rothvoss and Sanita (at STOC 2010) gave a 1.39-approximation for the Steiner tree problem, using a hypergraph-based linear programming relaxation. They also upper-bounded its integrality gap by 1.55. We describe a shorter proof of the same integrality gap bound, by applying some of their techniques to a randomized loss-contracting algorithm.

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Deeparnab Chakrabarty, Jochen Koenemann, David Pritchard. 2010-06-11. Integrality Gap of the Hypergraphic Relaxation of Steiner Trees: a short proof of a 1.55 upper bound. https://arxiv.org/abs/1006.2249

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