Combining Two Worlds: Parameterised Approximation for Vertex Cover

  • Ljiljana Brankovic
  • Henning Fernau
Part of the Lecture Notes in Computer Science book series (LNCS, volume 6506)


We explore opportunities for parameterising constant factor approximation algorithms for vertex cover. We provide a simple algorithm that works on any approximation ratio of the form \(\frac {2l+1}{l+1}\) and has complexity that outperforms an algorithm by Bourgeois et al. derived from a sophisticated exact parameterised algorithm. In particular, for l = 1 (factor 1.5 approximation) our algorithm runs in time \(\mathcal{O}^{*}(1.09^{k})\). Additionally, we present an improved polynomial-time approximation algorithm for graphs of average degree four.


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© Springer-Verlag Berlin Heidelberg 2010

Authors and Affiliations

  • Ljiljana Brankovic
    • 1
  • Henning Fernau
    • 2
  1. 1.School of Electrical Engineering and Computer ScienceThe University of NewcastleCallaghanAustralia
  2. 2.Fachbereich 4, Abteilung InformatikUniversität TrierTrierGermany

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