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作者：Shechter, Steven M.; Bailey, Matthew D.; Schaefer, Andrew J.; Roberts, Mark S.
作者单位：University of British Columbia; Bucknell University; Pennsylvania Commonwealth System of Higher Education (PCSHE); University of Pittsburgh
摘要：The question of when to initiate HIV treatment is considered the most important question in HIV care today. Benefits of delaying therapy include avoiding the negative side effects and toxicities associated with the drugs, delaying selective pressures that induce the development of resistant strains of the virus, and preserving a limited number of treatment options. On the other hand, the risks of delayed therapy include the possibility of irreversible damage to the immune system, development o...
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作者：Yao, Jian; Adler, Ilan; Oren, Shmuel S.
作者单位：University of California System; University of California Berkeley
摘要：A model of two-settlement electricity markets is introduced, which accounts for flow congestion, demand uncertainty, system contingencies, and market power. We formulate the subgame perfect Nash equilibrium for this model as an equilibrium problem with equilibrium constraints (EPEC), in which each firm solves a mathematical program with equilibrium constraints (MPEC). The model assumes linear demand functions, quadratic generation cost functions, and a lossless DC network, resulting in equilib...
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作者：Banker, Rajiv D.; Natarajan, Ram
作者单位：Pennsylvania Commonwealth System of Higher Education (PCSHE); Temple University; University of Texas System; University of Texas Dallas
摘要：A DEA-based stochastic frontier estimation framework is presented to evaluate contextual variables affecting productivity that allows for both one-sided inefficiency deviations as well as two-sided random noise. Conditions are identified under which a two-stage procedure consisting of DEA followed by ordinary least squares (OLS) regression analysis yields consistent estimators of the impact of contextual variables. Conditions are also identified under which DEA in the first stage followed by m...
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作者：Chao, Xiuli; Zipkin, Paul H.
作者单位：University of Michigan System; University of Michigan; Duke University
摘要：Transportation and production contracts often specify the frequency and volume reserved by the supplier for a particular customer's deliveries. This practice motivated Henig et al. ( Henig, M., Y. Gerchak, R. Ernst, D. Pyke. 1997. An inventory model embedded in designing a supply contract. Management Sci. 43 184-189) to study a periodic-review inventory-control model where ordering cost is zero if the order quantity does not exceed a given contract volume and is linear in the excess quantity o...
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作者：Cook, Wade D.; Zhu, Joe
作者单位：York University - Canada; Worcester Polytechnic Institute
摘要：Assurance region (AR) restrictions on multipliers in data envelopment analysis (DEA) have been applied extensively in many performance measurement settings. They facilitate the derivation of multiplier values that reflect the reality of the problem situation under study. In measuring the operational efficiency of bank branches, for example, output multipliers would generally represent unit processing times for branch transactions such as deposits. AR restrictions on these multipliers are inten...
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作者：Ohsawa, Yoshiaki; Ozaki, Naoya; Plastria, Frank
作者单位：University of Tsukuba; Vrije Universiteit Brussel
摘要：A facility must be located within a given region taking two criteria of equity and efficiency into account. Equity is sought by minimizing the inequality in the facility-inhabitant distances, as measured by the sum of the absolute differences between all pairs of squared Euclidean distances from inhabitants to the facility. This measure meets the Pigou-Dalton condition of transfers and can easily be minimized. Efficiency is measured through optimizing the sum of squared inhabitant-facility dis...
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作者：Nuyens, Misja; Wierman, Adam; Zwart, Bert
作者单位：Vrije Universiteit Amsterdam; California Institute of Technology; University System of Georgia; Georgia Institute of Technology
摘要：Recently, the so-called class of SMART scheduling policies has been introduced to formalize the common heuristic of biasing toward small jobs. We study the tail of the sojourn-time (response-time) distribution under both SMART policies and the foreground-background policy (FB) in the GI/GI/1 queue. We prove that these policies behave very well under heavy-tailed service times. Specifically, we show that the sojourn-time tail under all SMART policies and FB is similar to that of the service-tim...
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作者：Chu, Leon Yang; Shen, Zuo-Jun Max
作者单位：University of Southern California; University of California System; University of California Berkeley
摘要：Following the multistage design approach, we propose two asymptotically efficient truthful double auction mechanisms, the BC-LP mechanism and the MBC mechanism, for an exchange market with many buyers and sellers. In this market, each buyer wants to procure a bundle of commodities and each seller supplies one unit of a commodity. Furthermore, various transaction-related costs will be incurred when a buyer trades with a seller. We prove that under both mechanisms, truthful bidding is a dominant...
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作者：Granot, Daniel; Yin, Shuya
作者单位：University of British Columbia; University of California System; University of California Irvine
摘要：We analyze the effect of price and order postponement in a decentralized newsvendor model with multiplicative and price-dependent demand, wherein the manufacturer sets the wholesale price, and possibly offers a buyback rate, and the retailer determines the order quantity and retail price. Such postponement strategies can be used by the retailer by delaying his operational decisions ( order quantity and retail price) until after demand uncertainty is observed. We show how the equilibrium values...
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作者：Alizadeh, Farid; Eckstein, Jonathan; Noyan, Nilay; Rudolf, Gabor
作者单位：Rutgers University System; Rutgers University New Brunswick; Rutgers University System; Rutgers University New Brunswick; Sabanci University
摘要：We describe an optimization method to approximate the arrival-rate function of a nonhomogeneous Poisson process based on observed arrival data. We estimate the function by cubic splines, using an optimization model based on the maximum-likelihood principle. A critical feature of the model is that the splines are constrained to be nonnegative everywhere. We enforce these constraints by using a characterization of nonnegative polynomials by positive semidefinite matrices. We also describe versio...
