bluuebunny/crossref_metadata_2025_split huggingface dataset:
Presence and place of main ideas and examples in study texts
Authors: Beishuizen Jos , Asscher Jessica , Prinsen Fleur , Elshout‐Mohr Marianne 
Published: September 2003

Background: How indispensable are examples and main ideas in study texts? In research into comprehension of expository texts examples are sometimes considered as cognitive support, sometimes as seductive details. According to the cognitivist view, text comprehension is based on main ideas, whereas the constructivist view holds that examples are the basis of understanding.Aims: This study explored how text comprehension is influenced by main ideas and examples in study texts, in relation to Vermunt's (1992, 1998) ‘concrete elaboration’ learning style. In Experiment 1, concrete texts with many examples were compared with abstract texts with many main ideas. In Experiment 2, idea‐oriented texts, in which main ideas preceded examples, were compared with example‐oriented texts, in which examples preceded main ideas.Samples: In both experiments, undergraduate social sciences students studied various versions of an introductory text on educational psychology.Methods: The text contained sections with a varying number of relevant and irrelevant examples and with or without a main idea (Experiment 1), and sections with a main idea followed by examples, sections with a main idea without examples, or sections with examples followed by a main idea (Experiment 2). After studying the text, students completed a verbatim recognition test and an explanation test.Results: Best results were obtained after studying sections with a main idea and two or five examples. Irrelevant examples were detrimental to understanding. Students used examples to construct knowledge or to activate prior knowledge. Students with a strong habit of concrete elaboration used main ideas to recollect episodes of personal experience. This may interfere with understanding underlying concepts and principles by relating main ideas to examples in the text. Students with a low score on the concrete elaboration scale were sensitive to the presence of examples in the study text.Conclusion: In expository texts, examples are indispensable. The findings suggest that main ideas are useful, and, in order to prevent interference effects, the more so when they are put at the end of sections.
The influence of shyness on children's test performance
Authors: Crozier W. Ray , Hostettler Kirsten 
Published: September 2003

Background: Research has shown that shy children differ from their peers not only in their use of language in routine social encounters but also in formal assessments of their language development, including psychometric tests of vocabulary. There has been little examination of factors contributing to these individual differences.Aims: To investigate cognitive‐competence and social anxiety interpretations of differences in children's performance on tests of vocabulary. To examine the performance of shy and less shy children under different conditions of test administration, individually with an examiner or among their peers within the familiar classroom setting.Sample: The sample consisted of 240 Year 5 pupils (122 male, 118 female) from 24 primary schools.Method: Shy and less shy children, identified by teacher nomination and checklist ratings, completed vocabulary and mental arithmetic tests in one of three conditions, in a between‐subjects design. The conditions varied individual and group administration, and oral and written responses.Results: The conditions of test administration influenced the vocabulary test performance of shy children. They performed significantly more poorly than their peers in the two face‐to‐face conditions but not in the group test condition. A comparable trend for the arithmetic test was not statistically significant. Across the sample as a whole, shyness correlated significantly with test scores.Conclusions: Shyness does influence children's cognitive test performance and its impact is larger when children are tested face‐to‐face rather than in a more anonymous group setting. The results are of significance for theories of shyness and have implications for the assessment of schoolchildren.
When teachers go the extra mile: Foci of organisational identification as determinants of different forms of organisational citizenship behaviour among schoolteachers
Authors: Christ Oliver , Van Dick Rolf , Wagner Ulrich , Stellmacher Jost 
Published: September 2003

Background: Psychological variables should play an important role in determining teachers' involvement in behaviours not directly or formally forced by contracts. Organisational identification as proposed from the Social Identity Approach is examined as a possible determinant of organisational citizenship behaviour (OCB) among schoolteachers.Aim: The aim of the present study was to explore the relationships between different foci of organisational identification and different forms of OCB in schools.Sample: Data sets of altogether 447 German school teachers who filled in all relevant items in a cross‐sectional questionnaire are used for analyses in the present study.Methods: Standardised questionnaires measuring organisational identification and OCB were administered.Results: Exploratory and confirmatory factor analyses revealed the proposed foci of identification (i.e., career identification, team identification, and organisational identification), as well as different forms of OCB (i.e., OCB towards the own qualification, towards the team, and towards the organisation). Structural equation modelling supports the main hypothesis that foci of identification relate differentially to forms of OCB.Conclusions: The results emphasise the importance of organisational identification as a determinant of OCB in schools. Practical implications are discussed.
Secondary school teachers' attitudes towards and beliefs about ability grouping
Authors: Hallam Susan , Ireson Judith 
Published: September 2003

Background: Internationally and historically considerable research has been undertaken regarding the attitudes of secondary school teachers towards different types of ability grouping. There has been no recent research taking account of the changing educational context in the UK.Aims: This paper aims to explore secondary school teachers' attitudes and beliefs about ability grouping taking account of school type, gender, experience and qualifications.Sample: The sample comprised over 1,500 teachers from 45 schools divided into three groups based on their ability grouping practices in years 7‐9 (the students were aged 11‐14). The sample included all the lower school teachers of mathematics, science and English and a random sample of teachers from other subjects in each school.Methods: Teachers responded to a questionnaire which explored their attitudes towards ability grouping through the use of rating scales and open‐ended questions.Results: The findings showed that the teachers' beliefs broadly reflected research findings on the actual effects of ability grouping, although there were significant differences relating to the type of school they taught in and the subject that they taught. Separate analysis of school types showed that length of time teaching, individual school differences and teacher qualifications were also significant predictors of attitudes.Conclusions: Teachers' beliefs about ability grouping are influenced by the type of groupings adopted in the school where they work, the subject that they teach, their experience and qualifications. As pedagogical practices are known to be influenced by beliefs these findings have important implications for teacher training.
Learning styles: Self‐reports versus thinking‐aloud measures
Authors: Veenman Marcel V. J. , Prins Frans J. , Verheij Joke 
Published: September 2003

Background: Learning styles are often assessed through students' self‐reports on instruments such as Vermunt's Inventory of Learning Styles (ILS). Recent research, however, has questioned the adequacy of questionnaires for the assessment of learning styles.Aims: The objective of this paper is to evaluate methods of learning style assessment as a means for identifying students at risk. Therefore, the ILS as a self‐report instrument will be compared with the students' actual study processes, assessed through the thinking‐aloud method.Sample: In the first study 1,060 students from the Technical University of Delft participated. Thirty‐three of them were selected on the ILS for participation in the second study.Method: The ILS was administered to the 1,060 participants and their study results (GPA and credit points) were collected. Next, the selected 33 participants studied a technical text while thinking aloud. Knowledge acquisition was measured by means of a post‐test. Thinking‐aloud protocols were analysed on frequencies of study activities, thus representing process measures of learning styles.Results: The ILS proved to be a rather weak predictor of study results in Study 1. Results from Study 2 show hardly any correspondence between ILS and study process measures, although principal component structures of both measures were highly similar. Furthermore, study process measures outweighed the ILS in the prediction of study results (post‐test, GPA and credit points).Conclusions: Learning style theory was confirmed by results on the study process measures. The assessment of learning styles through self‐report instruments such as the ILS, however, should be reconsidered.
Experimental analysis of students' course selection
Authors: Babad Elisha , Tayeb Arik 
Published: September 2003

Background: Prior to every term, students must select courses (i.e., academic units of instruction within a degree programme) to determine their study programme. Course selection (CS) is a sequential decision‐making (DM) process — students weigh various types of information available about each course. Every decision influences the weighting of considerations for the next. This study is focused on three central dimensions of CS: Learning Value (low or high in being intellectually challenging, interesting and thought‐provoking), Lecturer's Style (low or high — exciting, charismatic and humorous versus dry, inflexible, unclear, etc.), and Course Difficulty (easy, moderate or hard).Aims: (1) To examine students' preferences for each dimension in five choices and in their sequential location (1st to 5th). (2) To trace compromises in dilemma situations after the desirable combinations had already been selected. (3) To investigate differential selection as a function of students' age, gender, and academic standing (average grades).Sample: Advanced undergraduates in various departments in an Israeli university (N=1,007).Method: In an experimental design, respondents were presented with 12 course descriptions representing 2×2×3 combinations, and asked to select five courses in a sequential order.Results: The 12 courses were found to be empirically divided into: ideal courses (2), first‐degree (4) and second‐degree (4) compromises, and rejected courses (2). Students avoided selecting hard courses unless they had no choice. Learning Value was the most preferred dimension, followed closely by Lecturer Style. Correlations showed that older and higher achieving students chose more difficult and high Learning Value courses.Comments: The discussion centred on the methodological issue of the effectiveness of an experimental design for the investigation of CS, conceptual issues concerning Course Difficulty in students' selection and evaluation, and applied issues concerning the availability of information about the three investigated dimensions to students in real‐life CS.
A nonparametric item analysis of a selected item subset of the Learning Process Questionnaire
Authors: Sachs John , Law Yin Kum , Chan Carol. K. K. 
Published: September 2003

Background: Although there have been numerous studies conducted on the psychometric properties of Biggs' Learning Process Questionnaire (LPQ), these have involved the use of traditional omnibus measures of scale quality such as corrected item total correlations, internal consistency estimates of reliability, and factor analysis. However, these omnibus measures of scale quality are sample dependent and fail to model item responses as a function of trait level. And since the item trait relationship is typically nonlinear, traditional factor analytic methods are inappropriate.Aims: The purpose of this study was to identify a unidimensional subset of LPQ items and examine the effectiveness of these items and their options in discriminating between changes in the underlying trait level. In addition to assessing item quality, we were interested in assessing overall scale quality with non‐sample dependent measures.Method: The sample was split into two nearly equal halves, and a undimensional subset of items was identified in one of these samples and cross‐validated in the other. The nonlinear relationship between the probability of endorsing an item option and the underlying trait level was modelled using a nonparametric latent trait technique known as kernel smoothing and implemented with the program TestGraf. After item and scale quality were established, maximum likelihood estimates of participants' trait level were obtained and used to examine grade and gender differences.Results: A undimensional subset of 16 deep and achieving items was identified. Slightly more than half of these items needed some of their options combined so that the probability of endorsing an item option as a function of increasing trait level corresponded to the ideal rank ordering of the item options. With this adjustment, scale quality as measured by the information function and standard error function was found to be good. However, no statistically significant gender differences were observed and, although statistically significant grade differences were observed, they were not substantively meaningful.Conclusions: The use of nonparametric kernel‐smoothing techniques is advocated over parametric latent trait methods for the analysis of attitudinal and psychological measures involving polychotomous ordered‐response categories. It is also suggested that latent trait methods are more appropriate than traditional test‐based measures for studying differential item functioning both within and between cultures. Nonparametric kernel‐smoothing techniques hold particular promise in identifying and understanding cross‐cultural differences in student approaches to learning at both the item and scale level.
Psychometric properties of the Movement Assessment Battery for Children‐Checklist as a screening instrument for children with a developmental co‐ordination disorder
Authors: Schoemaker Marina M. , Smits‐Engelsman Bouwien C.M. , Jongmans Marian J. 
Published: September 2003

Background: The Checklist of the Movement Assessment Battery for Children (MABC) was developed to screen children for movement difficulties in the school situation. However, the psychometric properties of the Checklist have not been investigated in detail.Aim: The psychometric properties of the M‐ABC Checklist were investigated including its usefulness as a screening instrument.Samples: A group of 120 children, 6 to 11 years old, randomly selected from mainstream schools and a group of 64 children, 6 to 9 years old, referred for assessment of their motor functioning.Methods: A reliability analysis was performed to investigate whether the 48 items of the Checklist measure the same construct. Construct validity was investigated by means of a factor analysis. And lastly, the sensitivity, specificity and positive predictive value of the Checklist were investigated by comparing the performance of children on both the Test and Checklist of the M‐ABC.Results: The items of the Checklist measure the same construct. Seven factors were obtained after factor analysis, revealing that the Checklist measures a broad range of motor skills. The Checklist met the standards for sensitivity in all age groups, except in the 8‐year‐old group, where too many children with motor problems were not detected. With the exception of the 6‐year‐old children, specificity was poor. The positive predictive value was acceptable, except for the 7‐year‐old children.Conclusion: the Checklist proved to meet standards for reliability and most aspects of validity. Its use by teachers for screening children with movement difficulties can be recommended.
Effect of gelation on the flow processability of poly(vinyl chloride)
Authors: Fujiyama Mitsuyoshi , Kondou Manabu 
Published: September 2003

AbstractThe processing of poly(vinyl chloride) (PVC) consists of fusion, flow, and solidification processes. In this study, we examined how gelation in the fusion process affected the processability in the following flow process. We prepared sheets with adjusted degrees of gelation (Gs) by rolling a rigid‐pipe‐formulation PVC compound with a degree of polymerization of 1050 by changing the milling temperature and time. The rheological properties, including viscosity, die swell, melt fracture, and entrance pressure loss (ΔPent), of the sheets were measured with a capillary rheometer, and the effect of gelation on the flow processability was studied. The viscosity slightly increased as the milling temperature and time increased, and hence, G increased. The flow activation energy showed a maximum at a shear rate around 100 s−1 and increased with increasing gelation. The die swell was larger when a sheet with a more advanced gelation was extruded at a higher temperature. Melt fracture easily occurred when a sheet with an advanced gelation was extruded at a low temperature. The critical shear rate at the onset of melt fracture changed by over 3 decades, depending on G. ΔPent increased linearly with G. The dependence of the rheological properties on the gelation was in the following order: melt fracture > die swell ≒ ΔPent > viscosity: The effect was larger for the elasticity than for the viscosity. The change in these rheological properties with increasing gelation was caused by a transition from particle flow to uniform molecular chain flow. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 1808–1824, 2003
Synthesis, structure, and thermophysical and mechanical properties of new polymers prepared by the cationic copolymerization of corn oil, styrene, and divinylbenzene
Authors: Li Fengkui , Hasjim Jovin , Larock Richard C. 
Published: September 2003

AbstractNew thermosetting polymeric materials were prepared by the cationic copolymerization of corn oil or conjugated corn oil with styrene and divinylbenzene initiated by boron trifluoride diethyl etherate or related modified initiators. The gel times ranged from a few minutes to hours or even days depending on the stoichiometry and curing temperatures. These polymeric materials possessed crosslink densities of 50 to 1.5 × 104 mol/m3 and glass‐transition temperatures of 30–99°C. The materials range from soft rubbers to tough and rigid plastics. The Young's moduli of these materials varied from 0.6 to 474 MPa, the ultimate tensile strengths varied from 0.5 to 17.6 MPa, the elongation at break percentages varied from 2 to 198%, the flexural strengths varied from 0.2 to 36 MPa, and the compressive strengths varied from 4.8 to 63.8 MPa. In addition to having commercially viable thermophysical and mechanical properties, these new materials also possessed good damping and shape‐memory properties, suggesting numerous, promising applications for these novel corn oil‐based polymeric materials. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 1830–1838, 2003
Formation of ordered microporous films with water as templates from poly(D,L‐lactic‐co‐glycolic acid) solution
Authors: Zhao Xiaoyong , Cai Qing , Shi Guixin , Shi Yanqiao , Chen Guanwen 
Published: September 2003

AbstractRecently a method that uses water droplets at the air–solution interface as an ordered template was reported for the preparation of ordered micrometer‐size honeycomb structures. Here we show that the method can also be used for formation of honeycomb‐like porous films from random copolymers with certain hydrophilicity, besides those polymers with defined structures such as block copolymers, starlike homopolymers, amd amphiphilic polymers. This demonstrates that the stabilization of water droplets is the key factor for the regular structure. Also we indicate that size and structure of the films can be regulated by such variables as concentration and atmospheric humidity. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 1846–1850, 2003
Synthesis of novel magnetic polymer microspheres with amphiphilic structure
Authors: Liu Xue‐Yong , Ding Xiao‐Bin , Zheng Zhao‐Hui , Peng Yu‐Xing , Long Xin‐Ping , Wang Xiao‐Chuan , Chan Albert S. C. , Yip C. W. 
Published: September 2003

AbstractNovel magnetic polymer microspheres with amphiphilic structure ranging in diameter from 5 to 80 μm were prepared by dispersion copolymerization of styrene and poly(ethylene oxide) acrylamide macromonomer (MPEO) in the presence of Fe3O4 magnetic fluid. The effects of various polymerization parameters on the average particle size were systematically investigated. The average particle size was found to increase with increasing initiator concentration. It also increased with decreasing stabilizer concentration and MPEO concentration. The content of the amino groups localized in the microspheres ranged from 0.01 to 0.25 mmol/g. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 1879–1884, 2003
Behavior of volatile depletion for LaRC™‐PETI‐5 amide acid/N‐methylpyrrolidinone solution
Authors: Hou T. H. , Costen R. C. 
Published: September 2003

AbstractThe fabrication of composites from polyimide precursors (polyamide acids) that involve condensation reactions requires the removal of volatiles (solvent and reaction by‐products) prior to consolidation in order to achieve a void‐free laminate. Volatile removal is commonly accomplished with a B‐stage processing step. In this study, a PETAA/NMP (phenylethynyl terminated amide acid in N‐methylpyrrolidinone) solution and prepreg were characterized using therogravimetric analysis (TGA) and microdielectrometry. A master weight loss profile was constructed by superimposing measurements at various heating rates. The TGA results correlated well with the dielectric ionic conductivities. Under the same thermal conditions, volatiles were depleted at slower rates from the wet prepreg than the neat resin solution. Dielectric properties were more sensitive to the residual volatile contents than the TGA measurements in both the neat resin and wet prepreg. Dielectric sensing technology was demonstrated to be a feasible tool for future volatile management in the fabrication of PETI composites. This study demonstrates that the combination of TGA and dielectrometry provides useful information to develop proper processing conditions for composite fabrication from prepregs containing volatiles. © Published 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 1906–1916, 2003