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作者：Behrens, DA; Caulkins, JP; Tragler, G; Feichtinger, G
作者单位：Technische Universitat Wien; University of Klagenfurt; Carnegie Mellon University; RAND Corporation
摘要：Drug use and related problems change substantially over time, so it seems plausible that drug interventions should vary too. To investigate this possibility, we set up a continuous time version of the first-order difference equation model of cocaine use introduced by Everingham and Rydell (1994), extended to make initiation an endogenous function of prevalence. We then formulate and solve drug treatment and prevention spending decisions in the framework of dynamic optimal control under differe...
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作者：Repenning, NP
作者单位：Massachusetts Institute of Technology (MIT)
摘要：Understanding the wide range of outcomes achieved by firms trying to implement Total Quality Management (TQM) and similar process improvement initiatives presents a challenge to management theory: A few firms reap sustained benefits from their programs, but most efforts fail and are abandoned. In this paper I study one dimension of this phenomenon: the role of impending layoffs in determining employee commitment to process improvement. Currently, the literature provides two opposing theories c...
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作者：Wang, YZ; Cohen, MA; Zheng, YS
作者单位：University System of Ohio; Case Western Reserve University; University of Pennsylvania
摘要：Consider a two-echelon repairable inventory system consisting of a central depot and multiple stocking centers. The centers provide parts replacement service to customers and replenish their inventory from the depot, following a one-for-one policy. The depot fills center replenishment orders on a first-come-first-serve basis. Defectives received at the centers are passed to the depot for repair and depot inventory replenishment. For this system, existing models (e.g., the METRIC model) usually...
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作者：Dasgupta, A; Ghosh, M
作者单位：Tufts University; Massachusetts System of Public Higher Education; Massachusetts Maritime Academy
摘要：To optimize large-scale queuing systems configurations, OR professionals typically use discrete event simulation packages to examine in detail the movement of entities through such systems, assuming stochastic but fixed arrival patterns. Demand aspects are, however, routinely ignored as few attempts are made to capture the feedback effect of queue performance on the arrival process. Econometricians, on the other hand, use a simultaneous equations estimation approach relying on past data, but t...
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作者：D'Amato, RM; D'Aquila, RT; Wein, LM
作者单位：RAND Corporation; Harvard University; Harvard University Medical Affiliates; Massachusetts General Hospital; Harvard University; Harvard University Medical Affiliates; Massachusetts General Hospital; Massachusetts Institute of Technology (MIT)
摘要：We analyze two joint decisions in the management of HIV-infected patients on antiretroviral therapy: how frequently to measure a patient's virus level, and when to switch therapy. The underlying stochastic model captures the initial suppression and eventual rebound of the virus level in the blood of a typical HIV-infected patient undergoing treatment. We consider two classes of policies: a viral load policy, which triggers a change in therapy when the current virus level divided by the smalles...
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作者：Mendelson, H; Whang, SJ
作者单位：Stanford University
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作者：Brynjolfsson, E; Smith, MD
作者单位：Massachusetts Institute of Technology (MIT)
摘要：here have been many claims that the Internet represents a new nearly frictionless market. Our research empirically analyzes the characteristics of the Internet as a channel for two categories of homogeneous products-books and CDs. Using a data set of over 8,500 price observations collected over a period of 15 months, we compare pricing behavior at 41 Internet and conventional retail outlets. We find that prices on the Internet are 9-16% lower than prices in conventional outlets, depending on w...
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作者：Pennings, JME; Smidts, A
作者单位：Wageningen University & Research; University of Illinois System; University of Illinois Urbana-Champaign; Erasmus University Rotterdam; Erasmus University Rotterdam - Excl Erasmus MC
摘要：Two major approaches to measuring risk attitude are compared. One, based on the expected I utility model is derived from responses to lotteries and direct scaling. The other measure is a psychometric approach based on Likert statements that produces a unidimensional risk attitude scale. The data are from computer-assisted interviews of 346 Dutch owner-managers of hog farms, who made decisions about their own businesses. While the measures demonstrate some degree of convergent validity, those m...
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作者：Zaric, GS; Brandeau, ML; Barnett, PG
作者单位：Western University (University of Western Ontario); Stanford University; Stanford University
摘要：We assess the cost-effectiveness of maintenance treatment for heroin addiction, with emphasis on its role in preventing HIV infection. The analysis is based on a dynamic compartmental model of the HIV epidemic among a population of adults, ages 18 to 44. The population is divided into nine compartments according to infection status and risk group. The model takes into account disease transmission from drug injection and sexual contacts. The health benefits of methadone maintenance and the resu...
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作者：Hazen, G
作者单位：Northwestern University
摘要：Stochastic trees are extensions of decision trees that facilitate the modeling of temporal uncertainties. Their primary application has been to medical treatment decisions. It is often convenient to present stochastic trees in factored form, allowing loosely coupled pieces of the model to be formulated and presented separately. Ln this paper, we show how the notion of factoring can be extended as well to preference components of the stochastic model. We examine updateable-state utility, a flex...
