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11.
In this article, we introduce three new distribution-free Shewhart-type control charts that exploit run and Wilcoxon-type rank-sum statistics to detect possible shifts of a monitored process. Exact formulae for the alarm rate, the run length distribution, and the average run length (ARL) are all derived. A key advantage of these charts is that, due to their nonparametric nature, the false alarm rate (FAR) and in-control run length distribution is the same for all continuous process distributions. Tables are provided for the implementation of the charts for some typical FAR values. Furthermore, a numerical study carried out reveals that the new charts are quite flexible and efficient in detecting shifts to Lehmann-type out-of-control situations.  相似文献   
12.
科技资源配置能力已成为长江地区城市化进程的重要推力。因此,在构建科技资源与城市化耦合系统评价指标体系的基础上,利用耦合协调度模型综合评价长江区域科技资源配置与城市化的交互耦合关系。结果显示:从时间维度看,研究期内长三角科技资源配置能力与城市化进程之间的耦合关系基本上处于磨合阶段,耦合协调度以低度协调耦合状态为主并逐步过渡到中度协调耦合状态;从空间维度看,长三角各城市的科技资源配置与城市化耦合协调度在极度协调耦合、高度协调耦合、中度协调耦合、低度协调耦合四个阶段均有分布,层级分明且大部分城市尚处于低度协调耦合状态。  相似文献   
13.
精算是保险发展的基础,是保险经营的技术支持。精算在国外有四百年的发展历史,引入中国只有二十年。要使精算技术在中国得到发展创新并为社会需要服务,必须了解精算思想产生的历史背景,厘清精算理论发展的脉络,真正把握精算思想的实质。基于此,介绍了精算各发展时期的主要代表人物及其学术思想,阐述精算技术对各时期保险发展的影响,同时对精算学与复利理论、数学、统计学、计算技术、金融经济学交叉融合的历史过程进行了分析述评。  相似文献   
14.
针对科技奖励评价的特点,根据改进D—S证据合成规则,将专家的评价指标值转化为指标的综合得分并形成决策矩阵;结合TOPSIS模型求解理想解和负理想解,计算距离和贴近度,对各评价项目进行综合排名。实证结果表明:该模型能够很好地解决科技奖励评价过程中的不确定性问题,为科技奖励综合评价提供了一种新的思路。  相似文献   
15.
This article is concerned with the proposal of a new prediction interval and band for the nonlinear regression model. The construction principle of this interval and band is based on an exact (the meaning of the term “exact” will be given later) confidence region for parameters of the nonlinear regression model. This region, fully described in Vila and Gauchi (2007 Vila , J.-P. , Gauchi , J.-P. ( 2007 ). Optimal designs based on exact confidence regions for parameter estimation of a nonlinear regression model . Journal of Statistical Planning and Inference 137 ( 9 ): 29352953 .[Crossref], [Web of Science ®] [Google Scholar]), provides a rigorous justification for the new prediction interval and band that we propose. This new band is then compared to the classical bands (which are asymptotic and thus approximate for small n), and also to the band based on the bootstrap resampling method. The comparison of these bands is undertaken with simulated and real data from predictive modeling in food science.  相似文献   
16.
There is a tremendous need in our technological society to train statisticians for all sectors of education, government, and industry. Because statistical training has largely been restricted to graduate schools, the profession is losing many good students to other fields of study. Members of the statistics community are encouraged to reach out to high-school students and undergraduate students to increase the awareness of statistics as a scientific field of study and as a professional career. The ASA Council of Chapters has recently completed a slide presentation entitled “Statistical Science: The Profession,” which was professionally developed to aid this endeavor. In addition, high-school teachers, high-school counselors, and professors of mathematics and science education are identified as important audiences for hearing this message and for broadening general public awareness of what our profession has to offer.  相似文献   
17.
Stereology typically concerns estimation of properties of a geometric structure from plane section information. This paperprovides a brief review of some statistical aspects of this rapidly developing field, with some reference to applications in the earth sciences. After an introductory discussion of the scope of stereology, section 2 briefly mentions results applicable when no assumptions can be made about the stochastic nature of the sampled matrix, statistical considerations then arising solelyfrom the ‘randomness’ of the plane section. The next two sections postulate embedded particles of specific shapes, the particular case of spheres being discussed in some detail.

References are made to results for ‘thin slices’ and other prob-ing mechanisms. Randomly located convex particles, of otherwise arbitrary shape, are discussed in section 5 and the review concludes with a specific application of stereological ideas to some data on neolithic mining.  相似文献   
18.
Ever since R. A. Fisher published his 1936 article , "Has Mendel's Work Been Rediscovered?", historians of both biclogy and statistics have been fascinated by the surprisingly high conformity between Gregor (Johann) Mendel's observed and expected ratios in his famous experiments with peas. Fisher's calculatftl x2 statistic of the experiments, taken as a whole, suggested that results on a par or better than those Mendel reported coultl only be expected to occur about three times in every 100,000 attempts. The ensuing controversy as to whether or not the good Father "sophisticated" his data has continued to this very day. In recent years the controversy has focused upon the more technical question of what underlying genetic arrangement Mendel actually studied.

The statistical issues of the controversy are exam:.led in am historical and comparative perspective. The changes the controversy has gone through are evaluated, and the nature of its current, more biological, status is briefly discussed.  相似文献   
19.
现阶段,我国步入了创新驱动引领升级的关键时期,科技创新受到了整个社会的空前重视。科技保险作为分散和转移科技风险的重要手段,可以为科技创新提供有力的风险保障。目前,我国科技保险工作已经进入全面推广阶段,虽然取得了一定的成效,但整体运行并不理想,科技企业参保率低,科技保险缺失严重。究其原因,主要在于制度供给不能适应科技企业对科技保险的需求,科技保险制度供求非均衡,在现行的科技保险制度下积聚着大量的潜在利润,而这些潜在利润既是科技保险制度非均衡的原因,又是科技保险制度创新的动力。  相似文献   
20.
构建军民融合型航空科研体系对于实现航空科技工业的军民一体化、促进航空科技进步、影响航空科技工业的市场竞争结构具有重要意义。目前,中国航空科研体系在军民融合方面存在的主要问题是科研体系不完善,没有独立的分别从事军用与民用航空基础研究的科研机构,军方没有自己的航空科研机构。因此需建立一个由管理机构、大学科研机构、军用与民用航空基础科研机构、航空工业企业等组成的军民融合型航空科研体系,并从完善航空科研体系、建立军地航空科研立项与管理的协调机制、建立招投标制度、培育军民融合型航空工业企业主体等几方面进行相应改革。  相似文献   
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