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作者:Lam, Henry; Zhang, Xinyu; Zhang, Xuhui
作者单位:Columbia University; Stanford University
摘要:Biased stochastic estimators, such as finite differences for noisy gradient estimation, often contain parameters that need to be properly chosen to balance impacts from the bias and the variance. Although the optimal order of these parameters in terms of the simulation budget can be readily established, the precise best values depend on model characteristics that are typically unknown in advance. We introduce a framework to construct new classes of estimators based on judicious combinations of...
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作者:Li, Michael Lingzhi; Bouardi, Hamza Tazi; Lami, Omar Skali; Trikalinos, Thomas A.; Trichakis, Nikolaos; Bertsimas, Dimitris
作者单位:Massachusetts Institute of Technology (MIT); Brown University; Massachusetts Institute of Technology (MIT)
摘要:We developed DELPHI, a novel epidemiological model for predicting detected cases and deaths in the prevaccination era of the COVID-19 pandemic. The model allows for underdetection of infections and effects of government interventions. We have applied DELPHI across more than 200 geographical areas since early April 2020 and recorded 6% and 11% two-week, out-of-sample median mean absolute percentage error on predicting cases and deaths, respectively. DELPHI compares favorably with other top COVI...
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作者:Brown, David B.; Zhang, Jingwei
作者单位:Duke University
摘要:Many stochastic dynamic programs (DPs) have a weakly coupled structure in that a set of linking constraints in each period couples an otherwise independent collection of subproblems. Two widely studied approximations of such problems are approximate linear programs (ALPs), which involve optimizing value function approximations that additively separate across subproblems, and Lagrangian relaxations, which involve relaxing the linking constraints. It is well known that both of these approximatio...
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作者:Balseiro, Santiago R.; Lu, Haihao; Mirrokni, Vahab
作者单位:Columbia University; Alphabet Inc.; Google Incorporated; University of Chicago
摘要:Online allocation problems with resource constraints are central problems in revenue management and online advertising. In these problems, requests arrive sequentially during a finite horizon and, for each request, a decision maker needs to choose an action that consumes a certain amount of resources and generates reward. The objective is to maximize cumulative rewards subject to a constraint on the total consumption of resources. In this paper, we consider a data-driven setting in which the r...
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作者:Chen, Xinyun; Liu, Yunan; Hong, Guiyu
作者单位:The Chinese University of Hong Kong, Shenzhen; North Carolina State University
摘要:We study a dynamic pricing and capacity sizing problem in a GI/GI/1 queue, in which the service provider's objective is to obtain the optimal service fee p and service capacity & mu; so as to maximize the cumulative expected profit (the service revenue minus the staffing cost and delay penalty). Because of the complex nature of the queueing dynamics, such a problem has no analytic solution so that previous research often resorts to heavy traffic analysis in which both the arrival and service r...
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作者:Curtis, Frank E.; Molzahn, Daniel K.; Tu, Shenyinying; Wachter, Andreas; Wei, Ermin; Wonge, Elizabeth
作者单位:Lehigh University; University System of Georgia; Georgia Institute of Technology; Northwestern University; Northwestern University; University of California System; University of California San Diego
摘要:A decomposition algorithm for solving large-scale security-constrained AC optimal power flow problems is presented. The formulation considered is the one used in the Advanced Research Projects Agency-Energy Grid Optimization Competition, Challenge 1, held from November 2018 through October 2019. Algorithmic strategies are proposed for contingency selection, fast contingency evaluation, handling complementarity constraints, avoiding issues related to degeneracy, and exploiting parallelism. The ...
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作者:Bekci, Recep Yusuf; Gumus, Mehmet; Miao, Sentao
作者单位:University of Waterloo; McGill University; University of Colorado System; University of Colorado Boulder
摘要:Motivated by our collaboration with one of the largest fast-fashion retailers in Europe, we study a two-echelon inventory control problem called the one-warehouse multistore (OWMS) problem when the demand distribution is unknown. This system has a central warehouse that receives an initial replenishment and distributes its inventory to multiple stores in each time period during a finite horizon. The goal is to minimize the total expected cost, which consists of shipment, holding, lost-sales, a...
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作者:Ata, Baris; Barjesteh, Nasser
作者单位:University of Chicago; University of Toronto
摘要:We consider a make-to-stock manufacturing system selling multiple products to price-sensitive customers. The system manager seeks to maximize the long-run average profit by making dynamic pricing, outsourcing, and scheduling decisions. First, she adjusts prices dynamically depending on the systemstate. Second, when the backlog ofwork is judged to be excessive, she may outsource new orders, thereby incurring outsourcing costs. Third, she decides dynamically which product to prioritize in the ma...
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作者:Bimpikis, Kostas; Mantegazza, Giacomo
作者单位:Stanford University
摘要:Two-sided platforms play an important role in reducing frictions and facilitating trade, and in doing so they increasingly engage in collecting and processing data about supply and demand. This paper establishes that platforms have an incentive to strategically disclose (coarse) information about demand to the supply side, as this can considerably boost their profits. However, this practice may also adversely affect the welfare of consumers. By optimally designing its information disclosure po...
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作者:Grabisch, Michel; Mandel, Antoine; Rusinowska, Agnieszka
作者单位:Paris School of Economics
摘要:We propose a model of the joint evolution of opinions and social relationships in a setting in which social influence decays over time. The dynamics are based on bounded confidence: social connections between individuals with distant opinions are severed, whereas new connections are formed between individuals with similar opinions. Our model naturally gives rise to strong diversity, that is, the persistence of heterogeneous opinions in connected societies, a phenomenon that most existing model...