对数正态分布参数的最大似然估计

利用最大似然估计法求出了对数正态分布两个参数的估计量,并讨论了它们的无偏性和相合性。     

A Short Note on Almost Sure Convergence of Bayes Factors in the General Set-Up

ABSTRACT

Although there is a significant literature on the asymptotic theory of Bayes factor, the set-ups considered are usually specialized and often involves independent and identically distributed data. Even in such specialized cases, mostly weak consistency results are available. In this article, for the first time ever, we derive the almost sure convergence theory of Bayes factor in the general set-up that includes even dependent data and misspecified models. Somewhat surprisingly, the key to the proof of such a general theory is a simple application of a result of Shalizi to a well-known identity satisfied by the Bayes factor. Supplementary materials for this article are available online.     

在局域网上进行较大型应用软件设计的实用技术研究

针对网络环境下应用软件编制过程中容易出现的问题，提出了几种实用的处理技术，如数据库应用的一致性、层次分配合理性、并发控制措施、避免幽灵问题以及文件属性控制等．对一些仍然困扰数据库应用方面的问题，探索了解决途径．     

A product-limit estimator for use with length-biased data

The following life-testing situation is considered. At some time in the distant past, n objects, from a population with life distribution F, were put in use; whenever an object failed, it was promptly replaced. At some time τ, long after the start of the process, a statistician starts observing the n objects in use at that time; he knows the age of each of those n objects, and observes each of them for a fixed length of time? ∞, or until failure, whichever occurs first. In the case where T is finite, some of the observations may be censored; in the case where T =∞, there is no censoring. The total life of an object in use at time ∞ is a length-biased observation from F. A nonparametric estimator of the (cumulative) hazard function is proposed, and is used to construct an estimator of F which is of the product-limit type. Strong uniform consistency results (for n → ∞) are obtained. An “Aalen-Johansen” identity, satisfied by any pair of life distributions and their (cumulative) hazard functions, is used in obtaining rate-of-convergence results.     

ESTIMATION OF SPATIAL ARMA MODELS

Spatial ARMA models are considered using the nonsymmetric half plane ordering on a lattice of data. A method is given for the estimation of the orders and the coefficients of such models under an identifiability condition and the condition that the beat linear predictor is the best predictor in the mean square sense. Under these conditions, the strong consistency of the estimators ia established. The usual methods for ARMA modelling in Time Series Analysis require estimation of the innovations. The method of this paper introduces an inveree model complementary to the original model so that the estimation of the innovations is avoided. This leads to a substantial reduction in the computational complexity in the two-dimensional case.     

公众环境关心与环境友好行为的非一致性研究——基于中国综合社会调查数据的分析

基于中国综合社会调查2010年数据,运用oprobit和biprobit模型探讨了公众的环境关心和环境友好行为是否一致,并分析公众的个体特征与其环境关心和行为一致性的关系。研究结果表明：①公众对环境关心并不必然会促进其生活中的环境友好行为。控制其他条件不变,老年人、女性、收入及受教育程度会提高公众环境关心与实施环境友好行为的概率;②在考虑公众的城乡和地区差异后,公众的收入、非农就业和受教育程度在提高公众的环境关心与环境友好行为的一致性上具有积极作用;[JP2]③总体上,公众的收入水平和受教育程度对其环境关心和环境友好行为一致性的作用最稳健,这意味着增加居民的收入、提高公众的教育水平对促进我国环境保护事业有重要意义。     

论先秦儒家心性论发展的天命线索

心性论发源于原始宗教,其源头可追溯至商初,而西周的天命观则明确了道德教化的天命依据（此即“德命观”）。周人的立国叙事中隐含着其天命观的两个重要分支：一为文、武受命,为“人为论”之渊薮;一为太王、王季受命,为“天意论”之理论根源。两者均承认天命的道德性,信奉善恶报应,坚持德福一致;其区别在于前者认为从善或作恶取决于人自身,而后者则认为心性的善恶由天而定。但自西周晚期起,“人为论”逐步沉寂,“天意论”日渐兴起。“天意论”的理论延伸是为“命定论”,孔子的天命观可为其代表,不过,孔子“圣人”神话的破灭却促使儒家德命观向“时命观”转化,而儒家的道德哲学也因此摆脱了功利主义的藩篱,进而获得独立性与自足性。     

Subset Selection in Linear Regression using Sequentially Normalized Least Squares: Asymptotic Theory

This article examines the recently proposed sequentially normalized least squares criterion for the linear regression subset selection problem. A simplified formula for computation of the criterion is presented, and an expression for its asymptotic form is derived without the assumption of normally distributed errors. Asymptotic consistency is proved in two senses: (i) in the usual sense, where the sample size tends to infinity, and (ii) in a non‐standard sense, where the sample size is fixed and the noise variance tends to zero.     

协同理论在大学英语写作教学中的应用研究

在对目前违背协同理论的教学方法进行反思的基础上,分析了大学生对英语写作的需求,就如何减少中式英语,遵循“学伴用随”原则,体现互动协同提出新的方案并进行实证研究.写作教学应抛开重视纠错、考试和语法的训练方式,用互动协同理论践行“学伴用随”原则并指导教学,同时通过强势协同,用大量的正确语言实践挤压学生犯错误的空间,以有效提高学生的语言应用能力.     

Discrimination analysis when the variates are grouped and observed in sequential order

Suppose that measurements Math', i = l,....,k, are consecutively taken on an individual at the prescribed costs C_i, i = l,....,k. the individual comes from one of the two populations H₁ and H₂, and it is desired to detect which population the individual belongs to. Given the loss incurreed in selecting population H_r when in fact it belongs to H_s, the prior probability P_r of H_r (r = 1,2), and assuming that H_r has the normal distribution N(µ_r, V), r = 1,2, we derive the sequential Bayesian solution of the discrimination problem when µ₁, µ₂ and V are known. When µ_r, V are unknown and must be estimated, we propose a solution which is asymptotic Bayesian with exponential convergence rate.