Abstract
Borodin, Linial, and Saks introduce a general model for online systems in [BLS92] called task systems and show a deterministic algorithm which achieves a competitive ratio of 2n−1 for any metrical task system with n states. We present a randomized algorithm which achieves a competitive ratio of e/(e−1)n−1/(e−1)≈1.5820n−0.5820 for any metrical task system of n states. For the uniform metric space, Borodin, Linial, and Saks present an algorithm which achieves a competitive ratio of 2H n, and they show a lower bound of H n for any randomized algorithm. We improve their upper bound for the uniform metric space by showing a randomized algorithm which is (H n/ln2+1≈1.4427H n +1)-competitive.
Research supported in part by NSF grant number CCR-9309456.
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© 1995 Springer-Verlag Berlin Heidelberg
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Irani, S., Seiden, S. (1995). Randomized algorithms for metrical task systems. In: Akl, S.G., Dehne, F., Sack, JR., Santoro, N. (eds) Algorithms and Data Structures. WADS 1995. Lecture Notes in Computer Science, vol 955. Springer, Berlin, Heidelberg. https://doi.org/10.1007/3-540-60220-8_59
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DOI: https://doi.org/10.1007/3-540-60220-8_59
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