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تسجيل مستخدم جديدApproximately Efficient Cost-Sharing Mechanisms
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نشر من قبل
Mukund Sundararajan
تاريخ النشر
2006
مجال البحث
الهندسة المعلوماتية
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English
تأليف
Tim Roughgarden
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We make three different types of contributions to cost-sharing: First, we identify several new classes of combinatorial cost functions that admit incentive-compatible mechanisms achieving both a constant-factor approximation of budget-balance and a polylogarithmic approximation of the social cost formulation of efficiency. Second, we prove a new, optimal lower bound on the approximate efficiency of every budget-balanced Moulin mechanism for Steiner tree or SSRoB cost functions. This lower bound exposes a latent approximation hierarchy among different cost-sharing problems. Third, we show that weakening the definition of incentive-compatibility to strategyproofness can permit exponentially more efficient approximately budget-balanced mechanisms, in particular for set cover cost-sharing problems.
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