Approximation Algorithms Fall Semester , 2003 Lecture 20 : Nov 17 , 2003
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چکیده
We will look at a greedy algorithm for the uncapacitated facility location problem. It has a similar flavor to the approximation algorithm for set cover, in that it uses the method of dual fitting. The greedy approach yields some of the strongest results for the facility location problem. The algorithm presented here has an approximation factor of 1.61 and is due to Jain et al. [1]. The best known factor for this problem currently is 1.52 and is due to Mahdian, Ye and Zhang [2]. Regarding hardness results, Guha and Khuller [3] showed that the best possible approximation factor for this problem is 1.463 assuming NP * DTIME[nO(loglogn)].
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تاریخ انتشار 2003