Principles and Practice of Scaled Difference Chi-Square Testing

We highlight critical conceptual and statistical issues and how to resolve them in conducting Satorra–Bentler (SB) scaled difference chi-square tests. Concerning the original (Satorra & Bentler, 2001 Satorra, A. and Bentler, P. M. 2001. A scaled difference chi-square test statistic for moment structure analysis. Psychometrika, 66: 507–514. [Crossref], [Web of Science ®] , [Google Scholar]) and new (Satorra & Bentler, 2010 Satorra, A. and Bentler, P. M. 2010. Ensuring positiveness of the scaled chi-square test statistic. Psychometrika, 75: 243–248. [Crossref], [Web of Science ®] , [Google Scholar]) scaled difference tests, a fundamental difference exists in how to compute properly a model's scaling correction factor (c), depending on the particular structural equation modeling software used. Because of how LISREL 8 defines the SB scaled chi-square, LISREL users should compute c for each model by dividing the model's normal theory weighted least-squares (NTWLS) chi-square by its SB chi-square, to recover c accurately with both tests. EQS and Mplus users, in contrast, should divide the model's maximum likelihood (ML) chi-square by its SB chi-square to recover c. Because ML estimation does not minimize the NTWLS chi-square, however, it can produce a negative difference in nested NTWLS chi-square values. Thus, we recommend the standard practice of testing the scaled difference in ML chi-square values for models M ₁ and M ₀ (after properly recovering c for each model), to avoid an inadmissible test numerator. We illustrate the difference in computations across software programs for the original and new scaled tests and provide LISREL, EQS, and Mplus syntax in both single- and multiple-group form for specifying the model M ₁₀ that is involved in the new test.     

论灌阳县丧葬仪式“大歌”的庞杂性特征

灌阳县丧葬仪式之中的“大歌”,纳数百桩事于一体,内容博而杂；集百千言为一歌,结构长而大,此二者相辅相成,造就了包罗灌阳历史和现实,收尽生活种种现象的长大篇章,同时也造就其庞杂性特征。这一特性,当地居民用一字概而括之,谓之曰“大”。     

专利技术主题分析:基于SAO结构的LDA主题模型方法

[目的/意义]改善现有专利技术主题分析方法主题辨识度低、主题词二义性、无法识别技术信息中的"问题"与相应"解决方案"等问题。[方法/过程]本文通过抽取专利文本中的SAO结构,并从SAO结构中识别"问题和解决方案"（P&S）模式,基于"bag of P&S"假设,构建基于"主语-行为-宾语"（subject-action-object,SAO）结构的LDA主题模型,实现对专利文献主题结构的识别和分析。[结果/结论]案例研究表明,该方法能够有效识别主题分布,并在主题辨识度和语义消岐方面较传统LDA模型具有较大优势。     

Baecklund Transformation and Localized Coherent Structure for the （2＋1）—Dimensional Asymmetric Nizhnik—Novikov—Veselov Equation

This article is concerned with the extended homogeneous balance method for studying the abundant lacalized solution structure of the (2 1)-dimensional asymmetric Nizhnik-novikov-Veselov equation.A Baecklund transformation was first obtained.and then the richness of the localized coherent structures was found,which was caused by the entrance of two variable-separated arbitrary functions,in the model.For some spectial choices of the arbitrary functions,it is shown that the localized structures of the model may be dromions,lumps,and rinmg solitons.     

Curriculating Powerful Knowledge for Public Managers and Administrators

Abstract

Public Management and Public Administration are important professions for an emerging democracy such as South Africa. They operate as the interface between state and public and are responsible for enacting many of the government's policies and social initiatives. Concerns about a lack of capacity in the sector suggest that those in these roles may be unable to meet the demands of the workplace. This article reports on a study that responded to calls for the curriculum to address such concerns by interrogating the knowledge structures of Public Management and Public Administration programmes in higher education. Interviews, textbooks and course guides were analysed to illuminate the forms of knowledge being legitimated in curricula. The study found that the focus on knowledge, skills and processes might be at the expense of a focus on the development of particular attributes or dispositions in the knowers. Furthermore, the knowledge level focus was limited in that it was highly contextualised and “light” on theory, raising questions about the acquisition of powerful knowledge needed for good governance and critical engagement in the public sector. The study recommends that both programmes include more conceptual knowledge; exposure to critical powerful forms of knowledge; and the development of particular attributes and dispositions.     

Optimal sizing of piezo-actuators for minimum-deflection design of frames under uncertain loads

Optimal piezo-actuator sizes and locations for a frame structure under bending load uncertainty are determined with the objective of minimizing the deflection under worst case of loading. The bending moments generated by the piezo-actuators are used for deflection control, i.e., to minimize the maximum deflection. The frame is subjected to a tip load which lies in an uncertainty domain with regard to its magnitude and direction. The specific uncertain loading studied in the present paper involves a load of given magnitude but of unknown direction, which should be determined to produce the highest deflection. The worst case of loading depends on the size and location of the actuators leading to a nested problem of optimization (design) and anti-optimization (uncertainty problem). Results are given for deterministic and uncertain loading conditions.     

浅议英语轭式修辞格

轭式修辞格(Zeugma)是一种用法较为独特的修辞手法。由于其使用不如其它的修辞方法那么普遍，所以很少有人去注意它。本文将对这一修辞格的分类及结构作一初步探讨。     

An Ode to Imre Lakatos: Quasi-Thought Experiments to Bridge the Ideal and Actual Mathematics Classrooms

This paper explores the wide range of mathematics content and processes that arise in the secondary classroom via the use of unusual counting problems. A universal pedagogical goal of mathematics teachers is to convey a sense of unity among seemingly diverse topics within mathematics. Such a goal can be accomplished if we could conduct classroom discourse that conveys the Lakatosian (thought-experimental) view of mathematics as that of continual conjecture-proof-refutation which involves rich mathematizing experiences. I present a pathway towards this pedagogical goal by presenting student insights into an unusual counting problem and by using these outcomes to construct ideal mathematical possibilities (content and process) for discourse. In particular, I re-construct the quasi-empirical approaches of six!4-year old students’ attempts to solve this unusual counting problem and present the possibilities for mathematizing during classroom discourse in the imaginative spirit of Imre Lakatos. The pedagogical implications for the teaching and learning of mathematics in the secondary classroom and in mathematics teacher education are discussed.     

如何提高英语四、六级的作文分数

写作是大学英语教学的难点之一,也是四、六级考试的重点之一。笔者认为在考试中,书写工整漂亮、词汇标新立异、造句与众不同以及布局独树一帜可以帮助考生提高四、六级的作文分数。     

Opportunity structures and educational marginality: the post-16 transitions of young people outside education and employment

This paper reports on findings from a three-year ethnographic study of 24 young people in northern England who were classified as not in education, employment or training (NEET), or at risk of becoming so. Drawing on conceptions of opportunity structure and educational marginality, the paper discusses the processes leading to young people becoming NEET after leaving school. It presents findings concerning the family backgrounds, school experiences, and educational attainment of participants, and traces their initial post-16 destinations and their pathways to NEET status. Although most participants did not become NEET immediately after leaving school, restricted labour market opportunities and a lack of high-quality education and training for middle- and low-attaining young people exacerbated social and educational disadvantage. Over time, participants became increasingly restricted to marginal forms of learning. The paper argues that a focus on opportunity structures provides a powerful way of understanding these processes, and that alongside sustained NEET status, educational marginality should be of equal concern to policy makers.