A Tale of Two Methods

  • Reuven Bar-Yehuda
  • Dror Rawitz
Part of the Lecture Notes in Computer Science book series (LNCS, volume 3895)


We describe two widely used methods for the design and analysis of approximation algorithms, the primal-dual schema and the local ratio technique. We focus on the creation of both methods by revisiting two results by Bar-Yehuda and Even—the linear time primal-dual approximation algorithm for set cover, and its local ratio interpretation. We also follow the evolution of the two methods by discussing more recent studies.


Approximation Algorithm Vertex Cover Minimal Solution Dual Solution 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 2006

Authors and Affiliations

  • Reuven Bar-Yehuda
    • 1
  • Dror Rawitz
    • 2
  1. 1.Department of Computer ScienceTechnionHaifaIsrael
  2. 2.Caesarea Rothschild InstituteUniversity of HaifaHaifaIsrael

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