On-Line Algorithms and the k-Server Conjecture
نویسنده
چکیده
The Work Function Algorithm, a natural algorithm for the k-server problem, is shown to have competitive ratio at most 2k− 1 for all metric spaces. It is also shown that the k-server conjecture, which states that there is an on-line algorithm for the k-server problem with competitive ratio k, holds for all metric spaces with k + 2 points. Furthermore, two refinements of competitive analysis are proposed and studied: diffuse adversaries and comparative analysis. They address successfully some of the drawbacks of competitive analysis.
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