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.


Approximation Algorithm Search Tree Average Degree Vertex Cover Approximation Factor 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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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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