Approximation Algorithms for Geometric Median Problems

نویسندگان

  • Jyh-Han Lin
  • Jeffrey Scott Vitter
چکیده

In this paper we present approximation algorithms for median problems in metric spaces and xed-dimensional Euclidean space. Our algorithms use a new method for transforming an optimal solution of the linear program relaxation of the s-median problem into a provably good integral solution. This transformation technique is fundamentally di erent from the methods of randomized and deterministic rounding [Rag, RaT] and the methods proposed in [LiV] in the following way: Previous techniques never set variables with zero values in the fractional solution to 1. This departure from previous methods is crucial for the success of our algorithms. Support was provided in part by an National Science Foundation Presidential Young Investigator Award CCR{9047466 with matching funds from IBM, by NSF research grant CCR{9007851, by Army Research O ce grant DAAL03{91{G{0035, and by the O ce of Naval Research and the Defense Advanced Research Projects Agency under contract N00014{91{J{4052, ARPA order 8225. The research was conducted while the author was at the Department of Computer Science, Brown University.

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عنوان ژورنال:
  • Inf. Process. Lett.

دوره 44  شماره 

صفحات  -

تاریخ انتشار 1992