椭圆轮廓的评定方法及其计算机模拟

给出了一个正确的数据处理方法,对已有的机械零件的椭圆轮廓的几何参数和线轮廓度误差评定理论的不足作了修正,并用计算机模拟方法对其进行了验证。     

Local estimation for varying-coefficient models with longitudinal data

Varying-coefficient models are very useful for longitudinal data analysis. In this paper, we focus on varying-coefficient models for longitudinal data. We develop a new estimation procedure using Cholesky decomposition and profile least squares techniques. Asymptotic normality for the proposed estimators of varying-coefficient functions has been established. Monte Carlo simulation studies show excellent finite-sample performance. We illustrate our methods with a real data example.     

Identifying Latent Structures in Panel Data

This paper provides a novel mechanism for identifying and estimating latent group structures in panel data using penalized techniques. We consider both linear and nonlinear models where the regression coefficients are heterogeneous across groups but homogeneous within a group and the group membership is unknown. Two approaches are considered—penalized profile likelihood (PPL) estimation for the general nonlinear models without endogenous regressors, and penalized GMM (PGMM) estimation for linear models with endogeneity. In both cases, we develop a new variant of Lasso called classifier‐Lasso (C‐Lasso) that serves to shrink individual coefficients to the unknown group‐specific coefficients. C‐Lasso achieves simultaneous classification and consistent estimation in a single step and the classification exhibits the desirable property of uniform consistency. For PPL estimation, C‐Lasso also achieves the oracle property so that group‐specific parameter estimators are asymptotically equivalent to infeasible estimators that use individual group identity information. For PGMM estimation, the oracle property of C‐Lasso is preserved in some special cases. Simulations demonstrate good finite‐sample performance of the approach in both classification and estimation. Empirical applications to both linear and nonlinear models are presented.     

中美快消品行业企业简介体裁对比分析

文章根据专门用途英语学派的体裁分析理论,构建了商务体裁研究理论框架,对30篇中美快消品行业企业简介进行了体裁对比分析。结果表明,中美快消品行业企业简介语步结构基本一致,但二者在语步和步骤的选择频率、介绍性语步和劝说性语步的实现形式上存在差异。      

The Experience-Earnings Profile: Productivity-Augmenting or Purely Contractual? Evidence from the UK

We test the human capital interpretation of the experience-earnings profile. Does the upward sloping portion of the experience-earnings profile reflect on-the-job training which in turn causes the experience-productivity profile to slope upwards, or do purely contractual factors determine the nature of life-cycle earnings. Herein, we provide additional evidence on the relationship between productivity and earnings by examining earnings differentials in the UK academic labor market for economists. Using a test first suggested by Mincer, we find that the empirical results are consistent with human capital theory. We find that, although the positive relationship between earnings and experience persists when individual productivity measures are included in the salary equations for lecturers and senior lecturers, the positive relationship becomes statistically insignificant when the same productivity measures are included in the salary equations for professors. For lecturers and senior lecturers, the experience-salary profile properly reflects the structure of the national pay scale rather than variations in individual research productivity. At the professor level, where individual salaries are not determined by a pay scale, the data support the human capital explanation of the positive experience-earnings profile.

Modified profile likelihood estimation for the Weibull regression models in survival analysis

In this study, adjustment of profile likelihood function of parameter of interest in presence of many nuisance parameters is investigated for survival regression models. Our objective is to extend the Barndorff–Nielsen’s technique to Weibull regression models for estimation of shape parameter in presence of many nuisance and regression parameters. We conducted Monte-Carlo simulation studies and a real data analysis, all of which demonstrate and suggest that the modified profile likelihood estimators outperform the profile likelihood estimators in terms of three comparison criterion: mean squared errors, bias and standard errors.     

应用范成法加工对称凸轮轮廓的研究

对称凸轮轮廓的加工方法有多种,但各有不足,为了克服原有的加工方法的缺陷,提出了范成法加工对称凸轮轮廓曲线的方法,并阐明了范成法加工对称凸轮轮廓曲线的原理及实现方法.利用范成法加工对称凸轮,不但解决了其他加工方法加工接拍长、加工成本高甚至无法加工的问题,而且加工精度高,操作简单可靠,可广泛用于各种批量对称凸轮的加工生产.     

英语中名词性间接回指的认知语义解析

根据兰盖克的认知语法,英语中名词性间接回指的语义本质是基体—侧重有机结合体。名词性间接回指含有两个基本构成元素,即先行项和名词性回指项,但二者不共指。回指项的语义预设了先行项的意义,先行项的语义就成为名词性间接回指的基体。分析不同类型的名词性间接回指的语义特征,并指出名词性间接回指的语义是存在于认知主体大脑中的心理实体,它必然受到认知主体的认知域的限制,所以名词性间接回指的解读存在一定的个体差异性。     

从目的论视角探析企业简介翻译错误及其成因

根据Nord对翻译错误的分类和我们的调研,认为当前国内企业简介英语译文存在的问题主要有语用、文化和语言三方面错误。其主要原因在于译者缺乏明确的翻译目的,没能把译文读者放在首位,只是一味追求译文与原文在形式上的对等。企业简介翻译应当遵循三个原则：目的原则、译文读者导向原则和合适原则。     

Exploring patterns of personal growth initiative and posttraumatic stress: A latent profile analysis

Objective: This study examined the inconsistent relationship found between personal growth initiative (PGI) and posttraumatic stress symptoms (PTSS) by exploring potential subgroups. In addition, after identifying the subgroups, potential predictors of these subgroups were examined. Participants: Participants were 534 undergraduate students who experienced a potentially traumatic event (PTE). Data collection occurred from March 2013 to December 2014. Methods: Because this was a preliminary study, archival data was used. Participants consisted of students who experienced a PTE within the past three years. Results: Latent profile analysis indicated a five-class model as the best-fitting model. Direct exposure and intentionality of the event were significant predictors of class membership; length of time since event and gender did not predict class membership. Conclusions: The current study provides a potential explanation of the inconsistent results between PGI and PTSS and also highlights the importance of acknowledging subgroups when utilizing PGI after a PTE.