Accelerated test system strength models based on Birnbaum–Saunders distribution: a complete Bayesian analysis and comparison

Several models for studies related to tensile strength of materials are proposed in the literature where the size or length component has been taken to be an important factor for studying the specimens’ failure behaviour. An important model, developed on the basis of cumulative damage approach, is the three-parameter extension of the Birnbaum–Saunders fatigue model that incorporates size of the specimen as an additional variable. This model is a strong competitor of the commonly used Weibull model and stands better than the traditional models, which do not incorporate the size effect. The paper considers two such cumulative damage models, checks their compatibility with a real dataset, compares them with some of the recent toolkits, and finally recommends a model, which appears an appropriate one. Throughout the study is Bayesian based on Markov chain Monte Carlo simulation.     

Comparison of estimators of the location parameter using pitman's closeness criterion

Necessary and sufficient conditions for a linear estimator to dominate another linear estimator of a location parameter under the Pitman's criterion of comparison are discussed. Consequently it is demonstrated that a linear biased estimator can not dominate a linear unbiased estimator under Pitman's criterion and that the sample mean is the Closest Linear Unbiased Estimator (CLUE). It is also shown that the ridge regression estimator with a known biasing constant can not dominate the ordinary least squares estimator. If an estimator δdominates an estimator δin the average loss sense then sufficient conditions are obtained under which δis also preferred over δunder Pitman's criterion. Further we obtain sufficient conditions under which preference under the Pitman's criterion will lead to preference under the mean squared error sense.     

THE CHOICE BETWEEN SETS OF REGRESSORS

This paper examines the choice of critical values for testing both non-sequential and nested sequential sets of constraints in the standard linear regression model. Modest increases in (e.g.) t-ratio critical values relative to their one-off values are often sufficient to maintain proper size. A Bayesian decision-theoretic approach, highlighted by the Schwarz (1978) criterion, provides a framework for deriving consistency and asymptotic local power properties of both forms of testing (data mining) algorithms.     

企业创新的执行过程研究

创新不是时髦的口号,创新重在切实地执行,而执行重在目标分解与层层落实。目前,从理论层面来讨论创新者居多,结合企业实际,从创新的执行层面讨论则相对较少。从企业创新执行角度,将创新的理念作为一个目标,分解为可执行的流程:企业分析—创新分析—创新需求评估—确定创新需求—企业创新制度设计—控制文档—企业创新制度执行—企业创新制度监控、反馈与有效性评估—识别和修正缺陷—流程和结果固化—持续执行。通过以上流程将创新融入企业,执行、固化并持续。     

翻译标准的多元性、动态性和模糊性

翻译标准是衡量译文质量优劣的一种尺度,古今中外关于翻译标准的论述异彩纷呈,但没有一个放之四海而皆准的标准。通过分析各种翻译标准发现,翻译标准难以统一的主要原因在于翻译标准的本质特性,即：翻译标准的多元性、动态性和模糊性。     

Decision Making in `Random in a Broad Sense' Environments

It is shown that the uncertainty connected with a `random in a broad sense' (not necessarily stochastic) event always has some `statistical regularity' (SR) in the form of a family of finite-additive probability distributions. The specific principle of guaranteed result in decision making is introduced. It is shown that observing this principle of guaranteed result leads to determine the one optimality criterion corresponding to a decision system with a given `statistical regularity'.     

AIN基片上重掺杂硼的多晶硅膜电阻率温度特性

研究了ＡｌＮ基片上重掺杂硼的多晶硅膜电阻率温度特性。实验发现，膜电阻率随温度变化呈现出从ＮＴＣ过渡到ＰＴＣ的Ｕ型特性，转折温度ＴＭ的位置依赖工艺条件的变化。理论分析表明：晶界势垒使膜电阻率在温度变化上存在一个极小值，极小值对应的转折温度正比于晶界势垒。     

论新课标下学生数学思维能力的培养

顺应新课程标准的要求，数学思维能力的培养必须在遵循概念、判断、推理等一般规律的基础上，着力改进数学教学评价方式，努力将数学课堂还原为学堂，将数学教学延伸到课外、校外，引领学生在生动的数学学习中生成数学思维能力．     

核心期刊的选刊依据及其冷思考

核心期刊产生于20世纪30年代的英国,它是期刊发展到一定历史阶段的必然产物,其理论依据是期刊集中与分散定律,即布拉德福定律。20世纪80年代中国科学院文献情报中心首先引进并开始研究核心期刊,其后一些研究单位也开展研究,取得了一系列开始性的成果。随着核心期刊影响力的不断扩大,并且这种影响力受期刊界和学术界的推波助澜,核心期刊在受到广泛关注的同时也引发了一些争议。不可否认,核心期刊确实存在一定的局限性,但它毕竟是一种客观存在,历史贡献功不可没,其积极的一面要远远大于其消极的一面。对待核心期刊应采取科学的态度,不能把它的作用推向极端,而应该克服它的局限性,科学合理地加以应用,使其在激活学术期刊市场、促进学术繁荣与发展方面发挥积极的作用。     

Properties of Bayes Factors Based on Test Statistics

Abstract.  This article examines the consistency, interpretation and application of Bayes factors constructed from standard test statistics. Primary conclusions are that Bayes factors based on multinomial and normal test statistics are consistent for suitable choices of the hyperparameters used to specify alternative hypotheses, and that such constructions can be extended to obtain consistent Bayes factors based on likelihood ratio statistics. A connection between Bayes factors based on likelihood ratio statistics and the Bayesian information criterion is exposed, as is a connection between Bayes factors based on F statistics and parametric Bayes factors based on normal-inverse gamma models. Similarly, Bayes factors based on chi-squared statistics for multinomial data are shown to provide accurate approximations to Bayes factors based on multinomial/Dirichlet models. An illustration of how the simple form of these Bayes factors can be exploited to generate easily interpretable summaries of the experimental 'weight of evidence' is provided.