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تسجيل مستخدم جديدApproximating Two-Stage Stochastic Supplier Problems
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نشر من قبل
Leonidas Tsepenekas
تاريخ النشر
2020
مجال البحث
الهندسة المعلوماتية
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English
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The main focus of this paper is radius-based (supplier) clustering in the two-stage stochastic setting with recourse, where the inherent stochasticity of the model comes in the form of a budget constraint. We also explore a number of variants where additional constraints are imposed on the first-stage decisions, specifically matroid and multi-knapsack constraints. Our eventual goal is to provide results for supplier problems in the most general distributional setting, where there is only black-box access to the underlying distribution. To that end, we follow a two-step approach. First, we develop algorithms for a restricted version of each problem, in which all possible scenarios are explicitly provided; second, we employ a novel emph{scenario-discarding} variant of the standard emph{Sample Average Approximation (SAA)} method, in which we crucially exploit properties of the restricted-case algorithms. We finally note that the scenario-discarding modification to the SAA method is necessary in order to optimize over the radius.
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