How to consider fractional counting and field normalization in the statistical modeling of bibliometric data: A multilevel Poisson regression approach

The numerical-algorithmic procedures of fractional counting and field normalization are often mentioned as indispensable requirements for bibliometric analyses. Against the background of the increasing importance of statistics in bibliometrics, a multilevel Poisson regression model (level 1: publication, level 2: author) shows possible ways to consider fractional counting and field normalization in a statistical model (fractional counting I). However, due to the assumption of duplicate publications in the data set, the approach is not quite optimal. Therefore, a more advanced approach, a multilevel multiple membership model, is proposed that no longer provides for duplicates (fractional counting II). It is assumed that the citation impact can essentially be attributed to time-stable dispositions of researchers as authors who contribute with different fractions to the success of a publication’s citation. The two approaches are applied to bibliometric data for 254 scientists working in social science methodology. A major advantage of fractional counting II is that the results no longer depend on the type of fractional counting (e.g., equal weighting). Differences between authors in rankings are reproduced more clearly than on the basis of percentiles. In addition, the strong importance of field normalization is demonstrated; 60% of the citation variance is explained by field normalization.     

知识管理下的分层多阶信息素质教学模式设计

根据信息素质教学发展及环境变化状况,基于知识管理理念设计出分层多阶信息素质教学模式。通过对教学对象、目标和实施方法的分层,采用循序渐进的课程和教学方法,应用型的教学评估和师资队伍,多功能的教材、网站等措施,实现信息素质教学对学生知识生长全过程的引导与帮助。     

Uncovering everyday dynamics in students’ perceptions of instructional quality with experience sampling

Within-student dynamics in perceptions of instructional quality have been neglected, although student states constitute a major share of these perceptions. The present study examined the structure and correlates of student state perceptions of the three basic dimensions, teacher support, cognitive activation, and classroom management. We conducted a three-week experience sampling study using state measures in four subjects (observations: n_mathematics = 2,681, n_physics = 1,555, n_German = 2,026, n_English = 1,835) and analyzed data from 372 German secondary school students (M_age = 15.3 years), conducting two-level confirmatory factor analyses. Against more parsimonious solutions, the postulated three-factor structure was confirmed within- and between-students across subjects, entailing 51% within-student variance on average. Similar to trait-like perceptions, state perceptions were positively related to grades and academic interest. Our results support the factorial and convergent validity of state student perceptions of instructional quality, expanding upon between-person-based literature and uncovering opportunities to enhance teaching effectiveness.     

An investigation of factors associated with letter-sound knowledge at kindergarten entry

Letter-sound knowledge is necessary for children to begin reading and writing, and kindergarteners who know only a few letter sounds are at risk for later reading difficulties. This study examines the letter-sound knowledge of 1197 first-time kindergarteners who were economically disadvantaged, in light of six hypotheses about letter-sound knowledge acquisition: (1) the letter-name structure effect hypothesis, (2) the letter-sound ambiguity hypothesis, (3) the letter-name knowledge hypothesis, (4) the own-name advantage hypothesis, and 5) the phonological awareness facilitation hypothesis, as well as the (6) interactions between phonological awareness and letter-name structure. Results using three-level multilevel modeling indicate that letter sounds have varying levels of difficulty and several letter- and child-related factors are associated with naming a letter sound correctly. Implications for instruction are discussed.     

多层线性模型的原理及应用

本文对多层线性模型 (HierarchicalLinearModels ,HLM)的理论缘起、应用范围以及其应用原理进行了阐述 ,在指出经典统计技术处理多层数据结构上的局限的同时 ,表明了多层线性模型在这方面的优越性。本文最后对多层线性模型的效果及局限性进行了简要分析。     

Examining the evidence from TIMSS: Gender differences in Year 8 science achievement in Australia

Australia's continuing participation in international science studies such as TIMSS provides a useful lens through which to monitor achievement in science over time. Gender differences in science were not evident in the early years of TIMSS but appear to be growing. This article examines gender differences in science achievement in early secondary schooling in Australia using data from the TIMSS 2003 study. The aim is to explore the cultural, social, structural and institutional factors that may differentially influence science achievement, with the aim of identifying which are more important for males and for females.     

Are both classroom autonomy support and structure equally important for students' engagement? A multilevel analysis

The current study was carried out within the framework of self-determination theory and aimed to investigate specific, additive and combined effects of teachers' autonomy support and structure on students' engagement. Using multilevel analyses, main effects and interaction of autonomy support and structure provided at the classroom level were tested on behavioral, cognitive and emotional engagement. 744 ninth grade students from 51 classes completed a questionnaire about their engagement during language classes and their perceptions of the teacher's provision of autonomy support and structure. The results highlight the links between classroom context, especially structure, and the three components of engagement. Autonomy support has a complementary role as it was associated with emotional engagement. These results improve our understanding of the relationships between learning environment and engagement and provide more accurate indications to teachers and educators regarding the most effective ways to enhance students' engagement.     

Observed lesson structure during the first year of secondary education: Exploration of change and link with academic engagement

This study investigates whether lesson structure (LS) matters and which components are important for academic engagement during the first grade of secondary education. Data from videoed lessons of 10 Dutch and 12 Indonesian teachers analyzed using an observation protocol show that six LS components are found, that between class and over measurement variability in LS is evident, and that on average LS change is not a linear function of time. Class differences over time do exist and several personal and contextual characteristics affect LS. Links between LS (student work time, reviewing and introducing new content) and academic engagement are evident.     

The Role of Students’ Home Language in Science Achievement: A multilevel approach

The present study aimed to identify the role of both student- and school-level characteristics in primary school students’ achievement in the science curriculum. As societies become more culturally and linguistically diverse, many students enter the classroom with a home language that is different from the language of instruction used at school. This study takes into account both the home language and literacy in the language of instruction in relation to student achievement in science subjects. Questionnaires, reading performance tests, and science achievement tests were administered to 1,761 fourth-grade students from 67 schools across Flanders (Belgium). Multilevel hierarchical regression analyses show that the home language and literacy in the language of instruction play an important role in science achievement at the student level, next to gender and socioeconomic status. Students with a home language that is different from the language of instruction experience difficulties with science subjects. Moreover, the higher students’ performance on reading comprehension and self-assessed proficiency in the language of instruction, the higher their score on science achievement tests. At the school level, a school's teachability expectations are one of the key factors related to students’ science achievement. Limitations of this study and future directions for research are discussed.     

Measuring the success of 'Playing for Success'

'Playing for Success' is a national initiative to establish Study Support Centres in professional football clubs, intended to support underachieving young people at key stages 2 and 3. The second year of the evaluation involved collection of data from pupils in 12 such Centres. Instruments were administered before and after attendance at the Centres, and measurements taken relating to literacy and numeracy, as well as attitude scales and self-assessments of ICT skills. Data were also obtained from a small 'control' group. Multilevel analysis of the results has given insights into the areas where the initiative appears to have had positive effects, and the other factors which may be associated with such effects.