Comparing Several Variances with a Control in Direction-mixed Families of Hypotheses

This article deals with simultaneous comparisons of k(k ? 1) populations with a control population with respect to variance in direction-mixed families of hypotheses. Computation of critical constants required for the implementation of the proposed procedures is discussed and selected values of the critical constants are tabulated. Power comparison of the proposed procedures with their existing competitors is carried out using Monte Carlo simulation. An example is given to illustrate the implementation of proposed procedures.     

An inclusion-consistent solution to the problem of absurd confidence statements: 2. Consistent nonexact-confidence-interval estimation

Two consistent nonexact-confidence-interval estimation methods, both derived from the consistency-equivalence theorem in Plante (1991), are suggested for estimation of problematic parametric functions with no consistent exact solution and for which standard optimal confidence procedures are inadequate or even absurd, i.e., can provide confidence statements with a 95% empty or all-inclusive confidence set. A belt C(·) from a consistent nonexact-belt family, used with two confidence coefficients (γ = inf_θ P_θ [ θ ? C(X)] and γ⁺ = sup_θ P_θ[θ ? C(X)], is shown to provide a consistent nonexact-belt solution for estimating μ₂ -μ₁ in the Behrens-Fisher problem. A rule for consistent behaviour enables any confidence belt to be used consistently by providing each sample point with best upper and lower confidence levels [δ⁺(x) ≥ γ⁺, δ(x) ≤ γ], which give least-conservative consistent confidence statements ranging from practically exact through informative to noninformative. The rule also provides a consistency correction L(x) = δ⁺(x)-δ(X) enabling alternative confidence solutions to be compared on grounds of adequacy; this is demonstrated by comparing consistent conservative sample-point-wise solutions with inconsistent standard solutions for estimating μ₂/μ₁ (Creasy-Fieller-Neyman problem) and $\sqrt {\mu _1^2 + \mu _2^2 }$, a distance-estimation problem closely related to Stein's 1959 example     

意义重释:民国文论体系话语的重要趋向

民国文论的体系建构负载着民国学人的历史想象与现实担当,砸破以往即兴体悟式的“私人话语”形态,在全面审视历史与时代的潮流中抒写社会的“公共话语”,发掘民族文化自信,民国文论展现出融汇中西、贯通古今的恢宏气象。民国学人兼顾中西、古今文论的各自特质,确立文论体系建构的逻辑起点与视角、探索可行的建设路径和策略,将错综复杂的民国文论现象纳入到民国文论的体系话语平台,展示民国文论继往开来的文化特质,它可以逐层解开中国现代文学研究领域诸多缠夹日久的学术命题,深远探究文论体系话语言说的基本规律。运用民国史视野来发掘民国文论资源,探究体系话语的言说模式与表达策略,具有范式重构和意义重释的色彩。     

联立Pell方程组x2-Dy2=-1和z2-(D+4)y2=-1

设D是正奇数.该文证明了:如果D≡1(mod8),则方程组x2-Dy2=-1和z2-(D 4)y2=-1没有整数解.     

投资者信心的测定及实证分析

投资者信心指数是在对投资者意向进行调查的基础上,将投资者的定性判断进行量化描述,从而测度不同时期投资意向变化的相对数。投资者信心指数的编制,旨在反映一定时期投资者的信心及其对未来投资发展的预期,从预期指数的前瞻性判断未来投资取向和经济走势,从而为各方面决策提供重要的参考数据。     

英军撤离前后新加坡的自立方略与成就

新加坡在1965年8月9日脱离马来西亚联邦后不久,又面临英国政府1967年宣布的提前撤军危机。这使得新加坡在军事、经济、人民生活等诸多方面面临措手不及的严重打击。面对这一严峻挑战,新加坡人民团结一致,在政府的明智决策指引下,建立了有效的防务力量,实现了经济的成功转型,凭借信心和自力更生的精神,走上了民族自立的道路,创造了亚洲的神话。     

Selection effects of source of contraceptive supply in an analysis of discontinuation of contraception: multilevel modelling when random effects are correlated with an explanatory variable

Summary. Conventional multilevel models assume that the explanatory variables are uncorrelated with the random effects. In some situations, this assumption may be invalid. One such example is the evaluation of a health or social programme that is non-randomly placed and/or in which participation is voluntary. In this case, there may be unobserved factors influencing the placement of the programme and the decision to participate that are correlated with the unobserved factors that influence the outcome of interest. The paper presents an application of a multiprocess multilevel model to assess the difference in rates of discontinuation of contraception between private and Government family planning providers, while accounting for the possibility that there may be unobserved individual and community level factors that influence both a couple's choice of provider and their probability of discontinuation.     

The Jackknife applied to incomplete blood sampling models

A nonparametric alternative to the extended parametric Satterthwaite method taking into account the correlation between samples obtained from the same animal is presented. Confidence intervals are computed using a modified jackknife standard error. The performance of the method is studied by means of simulation. This nonparametric method has a smaller coverage rate than the parametric one, but still close to the nominal confidence level. In addition, its confidence interval is shorter than that of the parametric method using the generalized Satterthwaite approximation. Copyright © 2003 John Wiley & Sons, Ltd.     

On the Optimality and Limitations of Buehler Bounds

In 1957, R.J. Buehler gave a method of constructing honest upper confidence limits for a parameter that are as small as possible subject to a pre‐specified ordering restriction. In reliability theory, these ‘Buehler bounds’ play a central role in setting upper confidence limits for failure probabilities. Despite their stated strong optimality property, Buehler bounds remain virtually unknown to the wider statistical audience. This paper has two purposes. First, it points out that Buehler's construction is not well defined in general. However, a slightly modified version of the Buehler construction is minimal in a slightly weaker, but still compelling, sense. A proof is presented of the optimality of this modified Buehler construction under minimal regularity conditions. Second, the paper demonstrates that Buehler bounds can be expressed as the supremum of Buehler bounds conditional on any nuisance parameters, under very weak assumptions. This result is then used to demonstrate that Buehler bounds reduce to a trivial construction for the location‐scale model. This places important practical limits on the application of Buehler bounds and explains why they are not as well known as they deserve to be.     

浅论历史教学中学生创造性思维的培养

从心理学角度探讨、分析在历史教学中如何培养学生的创造性思维,认为这关键是教师能善于在教学过程中渗透德育,从而激发学生的内在动力来实现调动其积极思维的目的。