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作者：Goyal, Vineet; Grand-Clement, Julien
作者单位：Columbia University
摘要：Markov decision processes (MDPs) are used to model stochastic systems in many applications. Several efficient algorithms to compute optimal policies have been studied in the literature, including value iteration (VI) and policy iteration. However, these do not scale well, especially when the discount factor for the infinite horizon discounted reward, lambda, gets close to one. In particular, the running time scales as O (1=(1 - lambda)) for these algorithms. In this paper, our goal is to desig...
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作者：de Ruiter, Frans J. C. T.; Zhen, Jianzhe; den Hertog, Dick
作者单位：Wageningen University & Research; Swiss Federal Institutes of Technology Domain; Ecole Polytechnique Federale de Lausanne; Swiss Federal Institutes of Technology Domain; ETH Zurich; University of Amsterdam
摘要：Adjustable robust minimization problems where the objective or constraints depend in a convex way on the adjustable variables are generally difficult to solve. In this paper, we reformulate the original adjustable robust nonlinear problem with a polyhedral uncertainty set into an equivalent adjustable robust linear problem, for which all existing approaches for adjustable robust linear problems can be used. The reformulation is obtained by first dualizing over the adjustable variables and then...
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作者：Vojnovic, Milan; Yun, Se-Young; Zhou, Kaifang
作者单位：University of London; London School Economics & Political Science; Korea Advanced Institute of Science & Technology (KAIST)
摘要：The problem of assigning ranking scores to items based on observed comparison data (e.g., paired comparisons, choice, and full ranking outcomes) has been of continued interest in a wide range of applications, including information search, aggregation of social opinions, electronic commerce, online gaming platforms, and, more recently, evaluation of machine learning algorithms. The key problem is to compute ranking scores, which are of interest for quantifying the strength of skills, relevancie...
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作者：Nadar, Emre; Akan, Mustafa; Debo, Laurens; Scheller-Wolf, Alan
作者单位：Ihsan Dogramaci Bilkent University; Carnegie Mellon University; Dartmouth College
摘要：We consider a single-product remanufacture-to-order system with multiple uncertain quality levels for used items, random procurement lead times, and lost sales. The quality level of a used item is revealed only after it is acquired and inspected; the remanufacturing cost is lower for a higher-quality item. We model this system as a Markov decision process and seek an optimal policy that specifies when a used item should be procured, whether an arriving demand for the remanufactured product sho...
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作者：Flamand, Tulay; Ghoniem, Ahmed; Maddah, Bacel
作者单位：Colorado School of Mines; University of Massachusetts System; University of Massachusetts Amherst; American University of Beirut
摘要：Given a store layout, product categories grouped into shelves, and historical sales data, we investigate how the allocation of product categories can be optimized in a fashion that guides in-store traffic and stimulates impulse buying. The latter constitutes an important shopping behavior that amounts to over 50% of the revenue in some retail settings. Considering a small-scale grocery store in Beirut, we analyze 40,000 customer receipts in order to relate in-store customer traffic to product ...
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作者：Chen, Xi; Wang, Yining
作者单位：New York University; University of Texas System; University of Texas Dallas
摘要：This paper studies a dynamic pricing problem undermodel misspecification. To characterize model misspecification, we adopt the epsilon-contamination model-the most fundamental model in robust statistics and machine learning. In particular, for a selling horizon of length T, the online epsilon-contamination model assumes that demands are realized according to a typical unknown demand function only for (1 - epsilon)T periods. For the rest of epsilon T periods, an outlier purchase can happen with...
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作者：Liu, Junyi; Pang, Jong-Shi
作者单位：Tsinghua University; University of Southern California
摘要：This paper proposes the use of a variant of the conditional value-at-risk (CVaR) risk measure, called the interval conditional value-at-risk (In-CVaR), for the treatment of outliers in statistical learning by excluding the risks associated with the left and right tails of the loss. The risk-based robust learning task is to minimize the In-CVaR risk measure of a random functional that is the composite of a piecewise affine loss function with a potentially nonsmooth difference-of-convex statisti...
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作者：Ozkan, Erhun; van Houtum, Geert-Jan
作者单位：Koc University; Eindhoven University of Technology
摘要：We study inventory and repair scheduling decisions of a maintenance service provider for repairable capital goods. Because of high downtime costs, the service provider keeps spare parts on stock to replace broken parts quickly. The service provider should determine the inventory level of spare parts for each component and the repair scheduling policy. Furthermore, in case of a stock-out, the service provider should decide whether to back-order the demand or execute an emergency repair, which i...
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作者：Lighta, Bar
作者单位：Microsoft
摘要：We study a pure-exchange incomplete-market economy with heterogeneous agents. In each period, the agents choose how much to save (i.e., invest in a risk-free bond), how much to consume, and which bundle of goods to consume while their endowments are fluctuating. We focus on a competitive stationary equilibrium (CSE) in which the wealth distribution is invariant, the agents maximize their expected discounted utility, and both the prices of consumption goods and the interest rate are market-clea...
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作者：Fontaine, Pirmin; Minner, Stefan
作者单位：Technical University of Munich; Technical University of Munich
摘要：The number of shipped parcels is continuously growing and e-commerce retailers and logistics service providers are seeking to improve logistics, particularly lastmile delivery. Since unused transportation space is a major problem in parcel distribution, one option is to improve the selection of the right parcel size for an order and the optimal packing pattern, which is known as the three-dimensional bin packing problem (3D-BPP). Further, the available portfolio of parcel types significantly i...
