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作者：Frazier, Peter I.
作者单位：Cornell University
摘要：We consider the indifference-zone (IZ) formulation of the ranking and selection problem with independent normal samples. In this problem, we must use stochastic simulation to select the best among several noisy simulated systems, with a statistical guarantee on solution quality. Existing IZ procedures sample excessively in problems with many alternatives, in part because loose bounds on probability of correct selection lead them to deliver solution quality much higher than requested. Consequen...
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作者：Tezcan, Tolga; Zhang, Jiheng
作者单位：University of Rochester; Hong Kong University of Science & Technology
摘要：We consider customer service chat (CSC) systems where customers can receive real time service from agents using an instant messaging (IM) application over the Internet. A unique feature of these systems is that agents can serve multiple customers simultaneously. The number of customers that an agent is serving determines the rate at which each customer assigned to that agent receives service. We consider the staffing problem in CSC systems with impatient customers where the objective is to min...
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作者：Cho, Soo-Haeng; Jang, Hoon; Lee, Taesik; Turner, John
作者单位：Carnegie Mellon University; Korea Advanced Institute of Science & Technology (KAIST); University of California System; University of California Irvine
摘要：This paper studies the problem of simultaneously locating trauma centers and helicopters. The standard approach to locating helicopters involves the use of helicopter busy fractions to model the random availability of helicopters. However, busy fractions cannot be estimated a priori in our problem because the demand for each helicopter cannot be determined until the trauma center locations are selected. To overcome this challenge, we endogenize the computation of busy fractions within an optim...
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作者：Akturk, M. Selim; Atamturk, Alper; Gurel, Sinan
作者单位：Ihsan Dogramaci Bilkent University; University of California System; University of California Berkeley; Middle East Technical University
摘要：Airline operations are subject to frequent disruptions typically due to unexpected aircraft maintenance requirements and undesirable weather conditions. Recovery from a disruption often involves propagating delays in downstream flights and increasing cruise stage speed when possible in an effort to contain the delays. However, there is a critical trade-off between fuel consumption (and its adverse impact on air quality and greenhouse gas emissions) and cruise speed. Here we consider delays cau...
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作者：Agrawal, Shipra; Wang, Zizhuo; Ye, Yinyu
作者单位：Microsoft; Microsoft India; University of Minnesota System; University of Minnesota Twin Cities; Stanford University
摘要：A natural optimization model that formulates many online resource allocation problems is the online linear programming ( LP) problem in which the constraint matrix is revealed column by column along with the corresponding objective coefficient. In such a model, a decision variable has to be set each time a column is revealed without observing the future inputs, and the goal is to maximize the overall objective function. In this paper, we propose a near-optimal algorithm for this general class ...
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作者：Kao, Yi-Hao; Van Roy, Benjamin
作者单位：Stanford University
摘要：We consider a problem involving estimation of a high-dimensional covariance matrix that is the sum of a diagonal matrix and a low-rank matrix, and making a decision based on the resulting estimate. Such problems arise, for example, in portfolio management, where a common approach employs principal component analysis (PCA) to estimate factors used in constructing the low-rank term of the covariance matrix. The decision problem is typically treated separately, with the estimated covariance matri...
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作者：Balinski, Michel; Laraki, Rida
作者单位：Centre National de la Recherche Scientifique (CNRS); Institut Polytechnique de Paris; Ecole Polytechnique; Centre National de la Recherche Scientifique (CNRS); Universite PSL; Universite Paris-Dauphine; Institut Polytechnique de Paris; Ecole Polytechnique
摘要：This article argues that the traditional model of the theory of social choice is not a good model and does not lead to acceptable methods of ranking and electing. It presents a more meaningful and realistic model that leads naturally to a method of ranking and electing-majority judgment-that better meets the traditional criteria of what constitutes a good method. It gives descriptions of its successful use in several different practical situations and compares it with other methods including C...
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作者：Johnson, Kris; Simchi-Levi, David; Sun, Peng
作者单位：Massachusetts Institute of Technology (MIT); Massachusetts Institute of Technology (MIT); Duke University
摘要：Scrip systems provide a nonmonetary trade economy for exchange of resources. We model a scrip system as a stochastic game and study system design issues on selection rules to match potential trade partners over time. We show the optimality of one particular rule in terms of maximizing social welfare for a given scrip system that guarantees players' incentives to participate. We also investigate the optimal number of scrips to issue under this rule. In particular, if the time discount factor is...
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作者：Delis, Manthos; Iosifidi, Maria; Tsionas, Efthymios G.
作者单位：University of Surrey; Lancaster University
摘要：This article proposes the estimation of the marginal cost of individual firms using semiparametric and nonparametric methods. These methods have a number of appealing features when applied to cost functions. The empirical analysis uses data from a unique sample of the California electricity industry for which we observe the actual marginal cost and estimate the marginal cost from these data. We compare the actual values of marginal cost with the estimates from semiparametric and nonparametric ...
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作者：Contreras, Ivan; Fernandez, Elena
作者单位：Concordia University - Canada; Universite de Montreal; Universitat Politecnica de Catalunya
摘要：This paper highlights how a general class of hub location problems can be modeled as the minimization of a real-valued supermodular set function. Well-known problems such as uncapacitated hub location, p-hub median, and hub arc location, among others, are shown to be particular cases of this class. Two integer programming formulations are introduced and compared. One uses path-based variables, frequently employed in hub location, whereas the other exploits properties of supermodular functions....
