Testing the Goodness of Fit of Parametric Regression Models with Random Toeplitz Forms

ABSTRACT: We introduce a class of Toeplitz‐band matrices for simple goodness of fit tests for parametric regression models. For a given length r of the band matrix the asymptotic optimal solution is derived. Asymptotic normality of the corresponding test statistic is established under a fixed and random design assumption as well as for linear and non‐linear models, respectively. This allows testing at any parametric assumption as well as the computation of confidence intervals for a quadratic measure of discrepancy between the parametric model and the true signal g;. Furthermore, the connection between testing the parametric goodness of fit and estimating the error variance is highlighted. As a by‐product we obtain a much simpler proof of a result of 34 ) concerning the optimality of an estimator for the variance. Our results unify and generalize recent results by 9 ) and 15 , 16 ) in several directions. Extensions to multivariate predictors and unbounded signals are discussed. A simulation study shows that a simple jacknife correction of the proposed test statistics leads to reasonable finite sample approximations.     

Evaluating employee assistance policy in an HMO-based alcoholism project.

One aspect of successful employee assistance program (EAP) implementation is the adoption of a formal, written policy, reflecting company commitment to EAP guidelines and goals. This study of criteria predictive of such policy adoption was conducted at the occupational alcoholism project of a New England health maintenance organization (HMO). Data on nearly 400 organizations contacted by occupational program consultants (OPCs) over a 20-month period were collected by questionnaire and interview. One third of these organizations adopted employee assistance policies and set about establishing formal programs. Stepwise multiple regression is the principal method used to pinpoint the correlates of policy adoption. Two of the most important of these are the attitudes of contact persons within the organization toward alcoholism and employee assistance programs, particularly their admission of alcohol problems within their social networks; and the consultants' persistence and marketing skills. The adopting organizations also had reputations for being progressive, and actively concerned about employee welfare; they tended to be large, their executives autonomous, and their union membership rates high. Inhibiting policy acceptance were fears that a written policy would jeopardize the reputation and image of the organization, and that an employee assistance program would remove internal control of personal procedures. The adequacy of the evaluative data and methods are discussed, and recommendations are offered in the interests of streamlining the efforts of OPCs and of achieving greater penetration of targeted organizations.     

中介语和反馈在外语学习中的作用

二语习得者在学习过程中不可避免地出现许多错误,这不仅是可以容忍的,而且是有益的。改正错误则是学习者的“中介语”向目的语趋近的一种方法。本文将对中介语的发展进行讨论,并从“反馈”这一角度来阐述它对外语教学的影响。     

张学良西北开发思想及其启示

张学良不仅是一位爱国将军,一位民族英雄,也是中国现代化建设的先驱。早在20世纪30年代,他就提出开发西北的一些设想,认为开发西北是复兴中国的基础,开发西北要革除私心,一致动员,借鉴美国的西部开发,同时要注意交通、环境、民族等问题。这些设想虽在当时由于缺乏现实条件难以实现,但是其现代化建设思想的重要组成部分,对今天的西部大开发仍有借鉴意义。     

辣椒常规品种子叶诱导植株再生体系的建立

以辣椒常规品种保加利亚尖椒与赤研6号为材料,探讨了激素、苗龄、有机成分、AgNO3等因素对子叶再生的影响.观察到PD添加剂对常规品种辣椒离体子叶不定芽的诱导分化及伸长有明显的促进作用.保加利亚尖椒的子叶分化频率达到100%,赤研6号的分化频率达到83%.芽伸长率分别为75%与55%,生根率达到80%以上.建立了辣椒常规品种的子叶离体高效再生体系.     

Dynamic factor models

Summary Factor models can cope with many variables without running into scarce degrees of freedom problems often faced in a regression-based analysis. In this article we review recent work on dynamic factor models that have become popular in macroeconomic policy analysis and forecasting. By means of an empirical application we demonstrate that these models turn out to be usefu in investigating macroeconomic problems.     

浅谈汉译英时主语的选择

本文主要分析了学生在做汉译英时主语常常丢失的情况。这是因为其一:汉语是话题优先型语言,话题与主语重合或话题出现而主语不出现的现象十分普遍;而英语是主语优先型语言,话题仅是一种特殊现象;其二:在做翻译练习时,主语选择的错误受到二语习得母语迁移的影响     

An analysis of variables affecting length of stay in foster care

The purpose of this paper was to find out whether the relationship between type of contact with agency and/or child in foster care and average number of contacts over time makes any difference in length of stay in foster care. Four types of contacts were examined: Family—Agency, Family Initiated—Agency, Social Worker—Initiated, and Family—Child. Results indicated that there were critical numbers for each contact type found to be statistically significant that would tend to reduce the length of the child's stay in foster care. The importance of contact during the first month of placement was emphasized.     

Scaling the prestige,authority, and income potential of college curricula

This paper develops the concept of “targeted education,” a theoretical ranking of college curricula, into a multidimensional framework. The new scales, based on the traditional stratification dimensions, prestige, authority, and income, are then used in a study of sex differences in the process of occupational achievement among men and women with college degrees. The targeted education scales predict occupational prestige and wages 7 years after the college degree, and they point out interesting differences between male and female attainment processes. In general, targeted education has a greater quantitative impact for men's occupational outcomes than for women's prestige and income, but results also suggest significant qualitative differences between men and women. A large proportion of women target their education toward, and end up in, an under-employed labor pool for the primary and secondary school system.     

肾叶唐松草微量元素和氨基酸的测定

本文利用原子吸收光谱法测定了中药肾叶唐松草中所含14种微量元素,利用氨基酸分析仪对它所含的氨基酸进行了鉴定及含量测定,并对根、茎、叶等不同部位的微量元素和氨基酸含量分别做了比较。