Greedy Approximation Algorithms for K-Medians by Randomized Rounding
نویسنده
چکیده
We give an improved approximation algorithm for the general kmedians problem. Given any > 0, the algorithm nds a solution of total distance at most D(1 + ) using at most k ln(n + n= ) medians (a.k.a. sites), provided some solution of total distance D using k medians exists. This improves over the best previous bound (w.r.t. the number of medians) by a factor of (1= ) provided 1= = n. The algorithm is a greedy algorithm, derived using the method of oblivious randomized rounding. It requires at most k ln(n+n= ) linear-time iterations. We also derive algorithms for fractional and weighted variants of the problem. Research partially funded by NSF CAREER award CCR-9720664.
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