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261.
汽车制造商和零件供应商可以节省巨大开支,但前提是双方要更为紧密地合作在一起麦肯锡的研究表明,北美汽车业每年在产品开发和组装过程中由于汽车生产商与供应商缺乏良好的计划和协调不当,造成了超过100亿美元的浪费。事实上.这只是较为保守的估算。因为我们的研究仅涵盖了供应商发生的成本,如:附加设计、生产工具最后改型和零件自身的附加成本。这还不包括因设计问题生产商需额外支付的改型费用、生产问题引发的车辆最终成本的增加或质保支出。这几项每年给汽车行业带来的浪费约为120亿美元。  相似文献   
262.
This paper applies Kim and Wardes (2004) stratified Warners randomized response model to Mangat and Singhs (1990) two-stage randomized response model. The proposed stratified randomized response model has an optimal allocation and a large gain in precision. Hence, the estimator based on the proposed method is more efficient than Kim and Wardes (2004) and Mangat and Singhs (1990) estimators under the conditions presented in both the case of completely truthful reporting and that of not completely truthful reporting by the respondents.  相似文献   
263.
The simulation problem is one of the most commonly used formats in computer-assisted instruction (CAI). In medical education, a patient simulation problem is known as a patient management problem (PMP). A number of computerized PMP systems are currently available. However, to date, there is no record of PMP systems having been developed using artificial intelligence. This is noteworthy since artificial intelligence techniques could help in the generation of more effective and intelligent instructional systems.

This paper analyzes and evaluates existing instructional simulation software in clinical medicine in terms of effective educational design attributes. Components of effective PMP systems thus identified are incorporated into a computerized instructional system which uses artificial intelligence techniques for teaching problem-solving and diagnostic skills to undergraduate medical students.  相似文献   

264.
This paper develops a rational expectations framework for interpreting the coefficient on age in a standard hedonic model. The model demonstrates that there are two components to the age coefficient: a pure cross-sectional depreciation component and a demand-side component that changes over time. We also show that a constant quality price index with age constant can be estimated by using any repeat sales database that contains the year of construction (or property age). When Fairfax County data are fitted to the model, the time series of age coefficients is non-stationary: they change from negative in the early 1980s to positive in the late 1980s; we infer that the demand-side component dominated in the latter period.  相似文献   
265.
Polyhedral combinatorics is a subarea of combinatorial optimization of increasing practical importance. It deals with the application of the theory of linear systems and linear algebra to combinatorial problems. The paper is not intended as a survey on polyhedral combinatorics but it reviews some of the main concepts and proof techniques.  相似文献   
266.
The HIV/AIDS epidemic has focused increased attention on catastrophic illnesses in the workplace, and because of the stigmas associated with HIV/AIDS, it raises three primary concerns for organizations: (1) organizational avoidance of legal sanctions and litigation; (2) the maintenance of organizational legitimacy; and (3) organizational protection of employee rights. Although many organizations adopt legalistic responses to cope with these concerns, the analysis presented in this article suggests that while legalistic approaches function well to protect organizational interests in terms of both legal liability and legitimacy, the are only partially able to protect employee rights. Drawing upon the limited literature on HIV/AIDS in the workplace, this article presents an agenda for future research on organizational responses to HIV/AIDS.  相似文献   
267.
Distribution-free tests for comparing several treatments with a control   总被引:1,自引:0,他引:1  
Abstract  In this paper we propose distribution-free treatments versus control tests for the one- and two-way classifications. The null distribution properties are shown to be equivalent to those of well-known statistics for which critical values have been extensively tabled. Asymptotic relative efficiencies with respect to corresponding normal theory competitors are derived and optimal designs for the allocation of experimental units to the treatments and control are obtained.  相似文献   
268.
Summary The problem of estimating the slope of a linear relationship between two jointly normally distributed random variables is considered when outliers may occur in the explanatory variable. It will be studied as a special case of an errors-in-variables problem where the explanatory variable is measured which a nonnormally distributed error. In this more general model and under certain conditions a consistent estimator can be given with a normal limiting distribution. Applications to cases of outliers in the explanatory variable will be presented.  相似文献   
269.
Abstract . Developing countries face an inconsistency between the need for more equitable distribution of income and wealth between classes and groups and the goals of an industrial relations system in which the trade unions have a systematic commitment to allied political parties to support them in exchange for some control over economic and social policy, or where unions compete with parties for popular support of certain social and political goals. This is designated as 'political unionism' in contradistinction to 'business unionism' where unions support any party whose overall strategy and objectives are most compatible. The analysis shows that ‘political unionism’ led, in Jamaica and in Trinidad and Tabago, to lags in growth which make industrial relations reform a necessity of an effective program of social change.  相似文献   
270.
Growth in U.S. agriculture is linked to the non-farm economy through domestic terms of trade and factor market adjustments. With almost stable input growth, the relatively large contributions from growth in Total Factor Productivity (TFP) are passed on to intermediate and final consumers in the form of declining real prices for primary farm products. The resulting net growth in the real value of farm output (GDP) is relatively low (0.25% per annum). The decomposition of TFP suggests that public agricultural stock of knowledge and infrastructure are robustly associated with TFP growth, while spill-overs from private agricultural and economy wide research and development (R and D) are positive but, relatively small.  相似文献   
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