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1.
本文研究统计假设检验问题中的渐近展开和功效损失,给出一阶渐近展开,二阶效率和功效损失,并且研究了建立在L-,R-,U-统计量及组合L-统计量上的检验问题。  相似文献   

2.
针对现有灰色关联理论的不足, 本文提出灰色关联的特征检验思路, 构建了矩阵型灰色关联度的特征检验方法。首先优化矩阵型灰色关联模型, 利用行为矩阵差值定义特征差异矩阵, 采用矩阵2范数构建关联度公式。而后分析特征差异矩阵的稳定性与趋势性, 利用变异系数形式构建稳定性系数, 利用最小二乘法估计趋势性系数, 两者共同组成矩阵型灰色关联度的特征检验方法。最后, 本文模型被应用于湖北省恩施州的长期多维贫困分析, 在与现有模型的比较中, 发现关联度评估结果有效区分了恩施州8个市县的贫困情况, 特征检验方法从贫困不确定性和趋势性两方面对结果进行补充, 验证了模型的可行性与实用性。  相似文献   

3.
本文给出存在集团检验误差时的集团抽样检验接受概率计算公式,该公式可用于设计抽样方案、分析集团检验错误对抽样方案的影响.采用计算机模拟抽样检验的方法对给出的公式加以验证,证明了该所给公式的正确性.同时通过对集团检验错误存在与否的抽样检验特征(OC)曲线的比较,指出:以往的集团抽样检验方案设计,都是在假设无检验误差前提下设计的,在抽样检验中,若存在检验错误,会严重影响抽样检验的接收概率,使抽样检验结果不能客观地反映检验批的质量.  相似文献   

4.
物证检验问题可以转化为双样本均值向量的检验和协方差矩阵的检验之统计理论问题 .对于检验统计量 T2、λ3,虽然 Hotelling对均值向量的检验给出了具有许多优良性质的 T2统计量 ,但它使用的前提条件是现场和嫌疑人的样本量必须同时大于特征数 ,这在物证检验中很难满足 ,本文的拓宽了使用条件 ,使其在物证检验中能够广泛使用 ;本文采用了统计模拟的方法构造了检验均值向量和协方差阵同时相等的统计量λ4 的上 1 0 0α%分位数表 ,这就为物证检验提供了新工具 ,将对于揭露和打击犯罪、保障国家的安全与社会的稳定具有重大的社会效益 .最后给出了应用实例 .  相似文献   

5.
《数理统计与管理》2015,(6):969-977
选取EU ETS第二阶段碳排放权配额EUA和核证减排量CER的现货和期货价格,运用递归OLS残差检验和CUSUM平方检验考察了欧盟碳价的动态变化路径,发现碳价序列具有明显的结构突变特征;进一步利用Bai-Perron方法检验了碳价发生结构突变的次数和时点,发现碳价在样本期内发生了两次结构突变,美国"次贷危机"、欧债危机和碳排放权配额过量是导致碳价发生结构突变的最主要原因。研究结果对我国构建碳金融体系、相关企业参与碳金融交易,以及相关部门监管碳交易市场,具有重要的启示作用。  相似文献   

6.
本文研究了在临床和流行病学中出现的K个独立含结构零的2×2列联表.利用风险比推导出基于Wald型,基于对数变换型以及基于Score型的三个检验统计量,以检验层间齐性假设,获得了分别基于这三个检验统计量的控制功效的样本量公式和数值实验结果.模拟研究表明基于Score检验和基于对数变换检验的样本量公式比基于Wald检验的样本量公式更精确,更能有效保证预先给定的功效.推广了基于列联表问题的假设检验方法.  相似文献   

7.
具有量化特征的物证检验问题可以转化为双样本均值向量和协方差矩阵同时检验的统计理论问题。文献〔1〕、〔2〕给出了该问题的统计量λ4,但至今无人求出其分布,更谈不上应用。本文采用了统计模拟的方法给出λ4的经验分布,由此计算出λ4的上100α%分位数表,并给出了相应的误差表和应用软件。这样,为物证检验提供了新工具,具有重大的社会效益。最后给出了应用实例。  相似文献   

8.
判断股市收益率波动的持续性问题通常归结为检验波动过程中是否存在着单位根。针对传统的单位根检验方法功效偏低,且检验的真实显著性水平容易失真的问题,本文采用随机波动率模型并利用改进的PP检验、KPSS检验,以及SIMEX检验方法对中国上证综合指数进行了实证研究.三种检验方法的结果都表明,股权分置改革后的上证综指收益率波动过程有单位根,波动呈现出很强的持续性.  相似文献   

9.
本文运用分数差分的方法研究了亚太地区主要股票市场的日股票价格.根据数据特征,我们运用了Robinson(1994)年提出的检验统计量的一种特殊形式对金融数据的单位根和不稳定性进行检验.结果证明,该地区股票价格长记忆行为各不相同但十分相似.  相似文献   

10.
非线性随机效应模型的异方差性检验   总被引:11,自引:0,他引:11  
随机效应模型广泛应用于刻画重复测量数据的特征.在该模型中,随机误差的方差包括受试群体内部及受试群体之间两项方差.Zhang和 Weiss 2000年研究了线性随机效应模型的异方差检验,本文对非线性随机效应模型,分别讨论了群体内、群体间和多变量的异方差性的检验问题,得到了检验的score统计量,并讨论了三种情形下,相应的score函数之间的关系.最后给出一个数值例子说明上述方法的有用性.  相似文献   

11.
本文将法庭科学中检验检材和比对是否同一的问题转化为多元统计的假设检验问题,将多元统计的检验方法应用到法庭科学中,取得了初步成果.  相似文献   

12.
Paul DeHart Hurd was a biology teacher and science supervisor in Colorado and California high schools and junior colleges for 20 years and a professor of science education at Stanford University for 22 years. He has authored 11 books and monographs on developments in the sciences and over 300 articles on various aspects of science education in the US and foreign countries. He has served on the National Science Foundation's Advisory Committee for Science Education and as a special educational consultant to the National Academy of Sciences, Commission on Life Sciences. Honors include the Apollo Award from the National Aeronautics and Space Agency, the Distinguished Contributions to Science Education Through Research Award from the National Association for Research in Science Teaching, and the Award for National Leadership in Science Education from the National Science Teachers Association. Dr. Hurd is currently focusing his writings on the history of science and technology education in the US over the past 200 years and current activities to modernize the precollege science curriculum.  相似文献   

13.
Conditions for rational and real-analytic functions of two real variables to be holomorphic are given in terms of holomorphic extendibility from families of circles. The first author was supported by the Israel Science Foundation, grant No. 279/02-1. The second author was partially supported by a grant from the Slovenian Ministry of Science and Technology. Both authors were supported by the Ministry of Science of Israel and the Ministry of Science and Technology of Slovenia, in the framework of the Program of Exchange by scientists.  相似文献   

14.
The concept of reversed hazard rate of a random life is defined as the ratio between the life probability density to its distribution function. This concept plays a role in analyzing censored data and is applicable in such areas as Forensic Sciences. In this investigation, we address the question of testing the reversed hazard rate where the null is that the reversed hazard rate is an assigned function while the alternative is that it is decreasing but not equal to the null function. Two approaches are discussed: one is based on the empirical distribution function while the other is based on the celebrated kernel methods. The limiting distributions of the test statistics are given and its asymptotic Pittman efficiencies are evaluated for well-known alternatives when the null distribution is exponential. Some other related problems are also addressed.  相似文献   

15.
The purpose of the study was to examine what science views were accepted or rejected by the Chinese university students. We administered the Thinking about Science Survey Instrument (TSSI) to 75 Chinese students in the Sichuan province who were enrolled in Science and Technology English classes. The TSSI focuses on nine key areas of science and aims at identifying whether an individual agrees or disagrees with a model science view. Chi‐square tests were applied to the data. Three idealized science views were found to be accepted regarding Science and the Economy, Science for All, and Science and Public Health. The same three science views were also found to be accepted in prior U.S. studies. Directions for further research are discussed including the examining views held by diverse populations and the potential development of a global view of science.  相似文献   

16.
中国科学技术大学原副校长、数学系教授龚昇先生2011年1月10日不幸病逝.本刊编委会、编辑部于2011年1月第1期发表《沉痛悼念著名数学家龚?教授》一文,简短介绍了他的生平和学术成就.本期特转载他为《中国科学技术大学数学五十年》一书所作的序,以纪念这位杰出的数学家和数学教育家.本文标题为编者所加.1958年,经中共中央...  相似文献   

17.
The aim of this paper is to frame Data Science, a fashion and emerging topic nowadays in the context of business and industry. We open with a discussion about the origin of Data Science and its requirement for a challenging mix of capability in data analytics, information technology, and business know‐how. The mission of Data Science is to provide new or revised computational theory able to extract useful information from the massive volumes of data collected at an accelerating pace. In fact, besides the traditional measurements, digital data obtained from images, text, audio, sensors, etc complement the survey. Then, we review the different and most popular methodologies among the practitioners of Data Science research and applications. In addition, because the emerging field requires personnel with new competences, we attempt to describe the Data Scientist profile, one of the sexiest jobs of the 21st Century according to Davenport and Patil. Most people are aware of the need to embrace Data Science, but they feel intimidated that they do not understand it and they worry that their jobs will disappear. We want to encourage them: Data Science is more likely to add value to jobs and enrich the lives of working people by helping them make better, more informed business decisions. We conclude this paper by presenting examples of Data Science in action in business and industry, to demonstrate the collection of specialist skills that must come together for this new science to be effective.  相似文献   

18.
Robert Yager is a native Iowan who was worked at the University of Iowa since 1956. He has served as president of seven national associations, including the National Science Teachers Association, School Science and Mathematics Association, the National Association of Biology Teachers, the Association for the Education of Teachers of Science, the National Association for Research in Science Teaching, Section Q of the American Association for the Advancement of Science, and the National Association of Science‐Technology‐Society. Yager has directed over 100 projects supported by the National Science Foundation, several research projects supported by the U.S. Department of Education, and several project evaluations. The University of Iowa has one of the largest graduate programs in the U.S., while also focusing on in‐service programs for science teachers and a model preservice program (which enjoyed NSF support for a 10‐year period). Yager has published over 500 books, monographs, and research reports. Currently, he is active with several research projects in Korea, Japan, Thailand, Malaysia, Israel, and Estonia.  相似文献   

19.
Book Reviews     
Book reviewed in this article: Dalmatz , Malvin S. and Wong , Harry K. a. Physical Science: Ideas and Investigations in Science. b. Teachers Manual—Physical Science: Ideas and Investigations in Science. c. Laboratory Data Book—Physical Science: Ideas and Investigations in Science. d. Idea 1—Predicting e. Idea 2—Matter f. Idea 3—Energy g. Idea 4—Interaction h. Idea 5—Technology Wong , Hahry K. and Dalmatz , Malvin S., Biology: Ideas and Investigations in Science.  相似文献   

20.
Summary By the use of conditioning, we extend previously obtained results on the asymptotic behavior of partial sums for certain triangular arrays of dependent random variables, known as Curie-Weiss models. These models arise naturally in statistical mechanics. The relation of these results to multiple phases, metastable states, and other physical phenomena is explained.Alfred P. Sloan Research Fellow. Research supported in part by National Science Foundation Grant MPS 76-06644A01Alfred P. Sloan Research Fellow. Research supported in part by National Science Foundation Grant MCS 77-20683 and by U.S.-Israel Binational Science FoundationResearch supported in part by National Science Foundation Grant PHY77-02172  相似文献   

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