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961.
The measurement of flows in the American labor market has challenged researchers for years. Several problems, including response variability, rotation group bias, and matching errors, hinder accurate measurement of the flows. The Bureau of the Census and the Bureau of Labor Statistics jointly sponsored a conference to examine these problems, present current research on solutions to the problems, and submit recommendations for improving the data. Recommendations include procedural changes in the Current Population Survey as well as new estimation techniques.  相似文献   
962.
Measuring the accuracy of diagnostic tests is crucial in many application areas including medicine and health care. Good methods for determining diagnostic accuracy provide useful guidance on selection of patient treatment, and the ability to compare different diagnostic tests has a direct impact on quality of care. In this paper Nonparametric Predictive Inference (NPI) methods for accuracy of diagnostic tests with continuous test results are presented and discussed. For such tests, Receiver Operating Characteristic (ROC) curves have become popular tools for describing the performance of diagnostic tests. We present the NPI approach to ROC curves, and some important summaries of these curves. As NPI does not aim at inference for an entire population but instead explicitly considers a future observation, this provides an attractive alternative to standard methods. We show how NPI can be used to compare two continuous diagnostic tests.  相似文献   
963.
In this paper, we propose two kernel density estimators based on a bias reduction technique. We study the properties of these estimators and compare them with Parzen–Rosenblatt's density estimator and Mokkadem, A., Pelletier, M., and Slaoui, Y. (2009, ‘The stochastic approximation method for the estimation of a multivariate probability density’, J. Statist. Plann. Inference, 139, 2459–2478) is density estimators. It turns out that, with an adequate choice of the parameters of the two proposed estimators, the rate of convergence of two estimators will be faster than the two classical estimators and the asymptotic MISE (Mean Integrated Squared Error) will be smaller than the two classical estimators. We corroborate these theoretical results through simulations.  相似文献   
964.
In this research, multiple dependent state and repetitive group sampling are used to design a variable sampling plan based on one-sided process capability indices, which consider the quality of the current lot as well as the quality of the preceding lots. The sample size and critical values of the proposed plan are determined by minimizing the average sample number while satisfying the producer's risk and consumer's risk at corresponding quality levels. In addition, comparisons are made with the existing sampling plans [Pearn and Wu (2006a Pearn, W. L., and C. W. Wu. 2006a. Critical acceptance values and sample sizes of a variables sampling plan for very low fraction of defectives. Omega: International Journal of Management Science 34 (1):90101.[Crossref], [Web of Science ®] [Google Scholar]), Yen et al. (2015 Yen, C. H., C. H. Chang, and M. Aslam. 2015. Repetitive variable acceptance sampling plan for one-sided specification. Journal of Statistical Computation and Simulation 85 (6):110216.[Taylor &; Francis Online], [Web of Science ®] [Google Scholar])] in terms of average sample number and operating characteristic curve. Finally, an example is provided to illustrate the proposed plan.  相似文献   
965.
对经典的最大流问题,研究了其电网络模拟情况,分析了各种最大流问题PSPICE模拟的实现,论证了方法的正确性,并给出了实例。文中也对其它一些问题,指出了电路模拟的可行性。文中结果表明,许多非电网络与系统的分析,也可以采用电路模拟的方法来予以简单直观地解决。  相似文献   
966.
Abstract: The authors derive empirical likelihood confidence regions for the comparison distribution of two populations whose distributions are to be tested for equality using random samples. Another application they consider is to ROC curves, which are used to compare measurements of a diagnostic test from two populations. The authors investigate the smoothed empirical likelihood method for estimation in this context, and empirical likelihood based confidence intervals are obtained by means of the Wilks theorem. A bootstrap approach allows for the construction of confidence bands. The method is illustrated with data analysis and a simulation study.  相似文献   
967.
本文提出了一种应用计算机对热电偶传输特性进行二次回归拟合的方法。该法以标准热电偶传输特性的高次方程为基础,用户根据所选用热电偶的实际工作温度范围与允许误差,应用本文所介绍的处理方法及程序使可获得一组能满足给定精度要求的热电偶二次回归拟合方程,且这组方程的数自为最少。  相似文献   
968.
对电磁力作用下的金属液体流动,建立了合理的数学模型,并数值模拟了流场情况。结果表明,磁场力可明显改变旋涡的形状。  相似文献   
969.
制造企业提升竞争力的途径探究——PDM与ERP的集成   总被引:4,自引:0,他引:4  
本文探讨了产品数据管理的定义及其主要任务 ,从企业信息化的角度 ,研究了产品数据管理与企业资源计划之间的互补性 ,给出了一个产品数据管理与企业资源计划的集成方案。  相似文献   
970.
Influence curves are defined for estimators of the ED50 in quantal bioassay, assuming a symmetic tolerance distribution. A definition of influence-curve robustness is suggested. Influence curves are obtained for L-,M- and R-estimators, and their robustness is investigated. The influence curve of the logistic maximum likelihood estimator is studied.  相似文献   
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