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61.
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A bilinear multivariate errors-in-variables model is considered. It corresponds to an overdetermined set of linear equations AXB=C, A∈ℝm×n, B∈ℝp×q, in which the data A, B, C are perturbed by errors. The total least squares estimator is inconsistent in this case.  An adjusted least squares estimator is constructed, which converges to the true value X, as m →∞, q →∞. A small sample modification of the estimator is presented, which is more stable for small m and q and is asymptotically equivalent to the adjusted least squares estimator. The theoretical results are confirmed by a simulation study. Acknowledgements. We thank two anonymous reviewers for their suggestions and corrections.? A. Kukush is supported by a postdoctoral research fellowship of the Belgian office for Scientific, Technical and Cultural Affairs, promoting Scientific and Technical Collaboration with Central and Eastern Europe.? S. Van Huffel is a full professor with the Katholieke Universiteit Leuven.? I. Markovsky is a research assistant with the Katholieke Universiteit Leuven.? This paper presents research results of the Belgian Programme on Interuniversity Poles of Attraction (IUAP V-22), initiated by the Belgian State, Prime Minister's Office – Federal Office for Scientific, Technical and Cultural Affairs of the Concerted Research Action (GOA) projects of the Flemish Government MEFISTO-666 (Mathematical Engineering for Information and Communication Systems Technology), of the IDO/99/03 project (K.U. Leuven) “Predictive computer models for medical classification problems using patient data and expert knowledge”, of the FWO projects G.0078.01, G.0200.00, and G0.0270.02.? The scientific responsibility is assumed by its authors.  相似文献   
63.
A method of combining survey data and Dairy Herd Improvement Association (DHIA) records to achieve low cost farm trials is presented. Farm trials and surveys of current practices and production responses are useful to identify yield gaps between expectations predicted from experimental findings and actual field results. Different management schemes can be ranked using subjective probabilities and stochastic dominance to enhance successful implementation of research findings and to increase the feedback between researchers, extension workers, and producers. A survey of current masitis control practices and expected milk yield response is the example. Combining survey results with DHIA records allowed estimating the relationship between somatic cell counts (SCC) and milk yield. Eliciting beliefs about the relationship between SCC and milk yield showed that producers agreed with predictions from the statistical model. Subjective probabilities about SCC and mastitis control practices showed that our sample of experts and producers consistently ranked the different practices but extension agents had no consensus about the the most or least effective ones.  相似文献   
64.
于畅海  张宇 《价值工程》2003,25(5):19-23
作为一种新的战略逻辑,价值创新逻辑已经在一些高成长企业的战略实践中显示出巨大效力。价值创新的利基和途径依企业的类别而异。本文将以企业价值链及其多重联系为切入点,提出中间投入品生产型企业实现高成长的价值创新利基和途径,并对价值创新的风险进行了初步的探讨。  相似文献   
65.
本文通过分析国外的经验,结合我国立法和司法实践,提出我国应建立破产犯罪罪名体系,并具体分析了破产犯罪罪名和立法体例.  相似文献   
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Transition patterns from school to work differ considerably across OECD countries. Some countries exhibit high youth unemployment rates, which can be considered an indicator of the difficulty facing young people trying to integrate into the labour market. At the same time, education is a time‐consuming process, and enrolment and dropout decisions depend on expected duration of studies as well as on job prospects with and without completed degrees. One way to model entry into the labour market is by means of job‐search models, where the job arrival hazard is a key parameter in capturing the ease or difficulty in finding a job. Standard models of job search and education assume that skills can be upgraded instantaneously (and mostly in the form of on‐the‐job training) at a fixed cost. This paper models education as a time‐consuming process, a concept which we call time‐to‐educate, during which an individual faces the trade‐off between continuing education and taking up a job.  相似文献   
68.
田宇 《物流科技》2002,25(3):7-11
指出部分物流网站存在虚假宣传的基础上,构建了物流服务信号传递分析模型,阐述了量化的服务承诺是有效的信号显示的观点,提出了物流企业服务承诺的制定原则。  相似文献   
69.
研究唐代小说的视角众多,从文化学角度将小说和时代文化结合起来是其中一种。唐前期小说集《纪闻》中蕴涵着丰富的文化信息。通过阅读《纪闻》小说文本,进一步探讨作品中所反映出的唐代宗教及民间信仰、女性生存状况、中外交流情况等。  相似文献   
70.
This study investigated the relationship between perception of environmental uncertainty (PEU) and environmental scanning behavior of Chief Executive Officers of 47 manufacturing firms in Nigeria. The results indicated that perceived uncertainty in the environment was significantly higher for the task environment sectors than for the remote environment sectors; and as perceived uncertainty increased in a sector of the environment, scanning frequency and scanning interests also increased. The results were compared with those of prior research in the area of environmental scanning. The results show both the economic and political legal sectors of the environment to be more salient for Nigerian manufacturing executives than for their American counterparts.  相似文献   
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