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作者：Adelman, Daniel
作者单位：University of Chicago
摘要：The Centers for Medicare and Medicaid Services (CMS) star rating methodology for publicly evaluating hospitals uses a latent variable model that is based on the presumption of a single, but unobservable, hospital-specific quality factor shared across a group of performance measures. Performance measures are given higher weight if they statistically appear to be more strongly correlated with this hidden factor. We show how this approach, when applied to measures that are weakly or not correlate...
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作者：Ghosal, Shubhechyya; Wiesemann, Wolfram
作者单位：Imperial College London
摘要：We study a variant of the capacitated vehicle routing problem (CVRP), which asks for the cost-optimal delivery of a single product to geographically dispersed customers through a fleet of capacity-constrained vehicles. Contrary to the classical CVRP, which assumes that the customer demands are deterministic, we model the demands as a random vector whose distribution is only known to belong to an ambiguity set. We then require the delivery schedule to be feasible with a probability of at least ...
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作者：Azizan, Navid; Su, Yu; Dvijotham, Krishnamurthy; Wierman, Adam
作者单位：California Institute of Technology
摘要：We consider a market run by an operator who seeks to satisfy a given consumer demand for a commodity by purchasing the needed amount from a group of competing suppliers with nonconvex cost functions. The operator knows the suppliers' cost functions and announces a price/payment function for each supplier, which determines the payment to that supplier for producing different quantities. Each supplier then makes an individual decision about how much to produce, in order to maximize its own profi...
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作者：Georghiou, Angelos; Tsoukalas, Angelos; Wiesemann, Wolfram
作者单位：McGill University; American University of Beirut; Imperial College London
摘要：Two-stage robust optimization problems, in which decisions are taken both in anticipation of and in response to the observation of an unknown parameter vector from within an uncertainty set, are notoriously challenging. In this paper, we develop convergent hierarchies of primal (conservative) and dual (progressive) bounds for these problems that trade off the competing goals of tractability and optimality: Although the coarsest bounds recover a tractable but suboptimal affine decision rule app...
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作者：Kettunen, Janne; Lejeune, Miguel A.
作者单位：George Washington University
摘要：The periodic selection of new product development (NPD) projects is a crucial operational decision. The main goals of start-up companies in NPD are to attain a reliable return level and deliver this return level fast. Achieving these goals is complicated because of uncertainties in projects' returns and durations. We develop new disjunctive stochastic programming models that capture the above-mentioned NPD goals. The first stochastic model is static, representing the traditional waterfall prod...
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作者：Ban, Gah-Yi
作者单位：University of London; London Business School
摘要：We revisit the classical dynamic inventory management problem of Scarf [Scarf H (1959b) The optimality of (s, S) policies in the dynamic inventory problem. Arrow KJ, Karlin S, Suppes P, eds. Mathematical Methods in the Social Science (Stanford University Press, Stanford, CA), 196-202.] from the perspective of a decision maker who has n historical selling seasons of data and must make ordering decisions for the upcoming season. We develop a nonparametric estimation procedure for the (S, s) poli...
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作者：Ouyang, Huiyin; Argon, Nilay Tanik; Ziya, Serhan
作者单位：University of Hong Kong; University of North Carolina; University of North Carolina Chapel Hill
摘要：The objective of this paper is to use mathematical modeling and analysis to develop insights into and policies for making bed allocation decisions in an intensive care unit (ICU) of a hospital during periods when patient demand is high. We first develop a stylized mathematical model in which patients' health conditions change over time according to a Markov chain. In this model, each patient is in one of two possible health stages, one representing the critical and the other representing the h...
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作者：Lu, Xuefei; Rudi, Alessandro; Borgonovo, Emanuele; Rosasco, Lorenzo
作者单位：Bocconi University; Universite PSL; Ecole Normale Superieure (ENS); Inria; University of Genoa; Massachusetts Institute of Technology (MIT); Istituto Italiano di Tecnologia - IIT
摘要：Kriging is one of the most widely used emulation methods in simulation. However, memory and time requirements potentially hinder its application to data sets generated by high-dimensional simulators. We borrow from the machine learning literature to propose a new algorithmic implementation of kriging that, while preserving prediction accuracy, notably reduces time and memory requirements. The theoretical and computational foundations of the algorithm are provided. The work then reports results...
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作者：Le Thi Khanh Hien; Sim, Melvyn; Xu, Huan
作者单位：University of Mons; National University of Singapore
摘要：We study a network fortification problem on a directed network that channels single-commodity resources to fulfill random demands delivered to a subset of the nodes. For given a realization of demands, the malicious interdictor would disrupt the network in a manner that would maximize the total demand shortfalls subject to the interdictor's constraints. To mitigate the risk of such shortfalls, a network's operator can fortify it by providing additional network capacity and/or protecting the no...
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作者：Haviv, Avery
作者单位：University of Rochester
摘要：In this paper I develop a cyclic value function iteration, which is an adjustment to the standard value function iteration. When using this algorithm, the inclusion of cyclic variables of any size into the state space of an infinite horizon Markov decision process does not increase the computational complexity of solving for the value function. This result is proven theoretically and shown to closely hold in practice using Monte Carlo simulations.
