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arXiv · 1204.0982

Approximability of the Vertex Cover Problem in Power Law Graphs

Mikael Gast·Mathias Hauptmann
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Abstract

In this paper we construct an approximation algorithm for the Minimum Vertex Cover Problem (Min-VC) with an expected approximation ratio of 2-f(beta) for random Power Law Graphs (PLG) in the (alpha,beta)-model of Aiello et. al., where f(beta) is a strictly positive function of the parameter beta. We obtain this result by combining the Nemhauser and Trotter approach for Min-VC with a new deterministic rounding procedure which achieves an approximation ratio of 3/2 on a subset of low degree vertices for which the expected contribution to the cost of the associated linear program is sufficiently large.

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Mikael Gast, Mathias Hauptmann. 2012-04-04. Approximability of the Vertex Cover Problem in Power Law Graphs. https://arxiv.org/abs/1204.0982

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