Vertex Cover Approximations: Experiments and Observations

  • Eyjolfur Asgeirsson
  • Cliff Stein
Part of the Lecture Notes in Computer Science book series (LNCS, volume 3503)


The vertex cover problem is a classic NP-complete problem for which the best worst-case approximation ratio is roughly 2. In this paper, we use a collection of simple reductions, each of which guarantees an approximation ratio of \(\frac{3}{2}\), to find approximate vertex covers for a large collection of test graphs from various sources. We explain these reductions and explore the interaction between them. These reductions are extremely fast and even though they, by themselves are not guaranteed to find a vertex cover, we manage to find a 3/2-approximate vertex cover for every single graph in our large collection of test examples.


Approximation Ratio Vertex Cover Extended Network Original Graph Linear Programming Relaxation 
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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Copyright information

© Springer-Verlag Berlin Heidelberg 2005

Authors and Affiliations

  • Eyjolfur Asgeirsson
    • 1
  • Cliff Stein
    • 1
  1. 1.Department of IEORColumbia UniversityNew York

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