Distinguishing teaching interactions of physically abusive from nonabusive parent-child dyads

Researchers using a variety of behavioral coding instruments have demonstrated differences between the interactions of physically abusive parent-child dyads and those of nonabusive pairs. Despite fair consistency among these findings, there remains controversy regarding the value of observation of parent-child interaction to the clinical evaluation of child abuse. This study was an investigation of the ability of child protective service workers to distinguish videotaped interactions of physically abusive parent-child dyads from interactions of nonabusive dyads. The interactions occurred as part of a teaching task and were nondisciplinary. The child protection workers achieved a 76% rate of accuracy in identifying the abuse status of the dyads based on observation of only three minutes of semi-structured videotaped interaction. Of the workers, 40% were accurate in classifying 100% of the dyads observed. Increased protective service experience was not associated with increased accuracy, but subjects with no experience in protective service performed at chance level only. The results of this study show that experienced professionals can detect interactional differences in nondisciplinary parent-child interchanges of abusive as compared to nonabusive dyads. This suggests that clinical observation of parent-child interaction may be one important diagnostic tool within a comprehensive evaluation of families suspected of physical child abuse.     

Towards Research-based Innovation and Reform: Singapore schooling in transition

The challenges facing the Singapore education system in the new millennium are unique and unprecedented in Asia. Demands for new skills, knowledges, and flexible competencies for globalised economies and cosmopolitan cultures will require system-wide innovation and reform. But there is a dearth of international benchmarks and prototypes for such reforms. This paper describes the current Core Research Program underway at the National Institute of Education in Singapore, a multilevel analysis of Singaporean schooling, pedagogy, youth and educational outcomes. It describes student background, performance, classroom practices, student artefacts and outcomes, and student longitudinal life pathways. The case is made that a systematic focus on teachers' and students' work in everyday classroom contexts is the necessary starting point for pedagogical innovation and change. This, it is argued, can constitute a rich multidisciplinary evidence base for educational policy.     

Preschool children's attention to environmental messages about groups: social categorization and the origins of intergroup bias

This study was designed to examine the effects of adults' labeling and use of social groups on preschool children's intergroup attitudes. Children (N=87, aged 3-5) attending day care were given measures of classification skill and self-esteem and assigned to membership in a novel (red or blue) social group. In experimental classrooms, teachers used the color groups to label children and organize the classroom. In control classrooms, teachers ignored the color groups. After 3 weeks, children completed multiple measures of intergroup attitudes. Results indicated that children in both types of classrooms developed ingroup-biased attitudes. As expected, children in experimental classrooms showed greater ingroup bias on some measures than children in control classrooms.     

Teaching Probability for Conceptual Change La Enseñanza De La Probabilidad Por Cambio Conceptual

This work presents a theoretical proposal for a methodology for the teaching of probability theory. The theoretical proposal has a dual inspiration: (1) the epistemological approach of Lakatos (1978b) regarding the quasi-empirical nature of mathematical theories; (2) the perspective of conceptual change for the teaching-learning process, as formulated by Strike and Posner (1992). The scientific content taught and the didactic methods used in the classroom should, according to this proposal, respect and conform to this dual inspiration. We also present an evaluation of the methodology in a real context: six Spanish high school classes of students aged 14–15. The main purpose of the research was to answer this question: Is our didactic proposal more effective than traditional methodology? We operatively identify the concept of traditional teaching, and establish several indicators of effectiveness: the mastery of elementary probability calculations, the quality of intuitive reasoning in probability, and the conceptual and attitudinal change produced. We found significant differences on all indicators, except for attitudinal change, in favour of the group that followed our proposal.     

First-grade cognitive abilities as long-term predictors of reading comprehension and disability status

In a sample of 195 first graders selected for poor reading performance, the authors explored four cognitive predictors of later reading comprehension and reading disability (RD) status. In fall of first grade, the authors measured the children's phonological processing, rapid automatized naming (RAN), oral language comprehension, and nonverbal reasoning. Throughout first grade, they also modeled the students' reading progress by means of weekly Word Identification Fluency (WIF) tests to derive December and May intercepts. The authors assessed their reading comprehension in the spring of Grades 1-5. With the four cognitive variables and the WIF December intercept as predictors, 50.3% of the variance in fifth-grade reading comprehension was explained: 52.1% of this 50.3% was unique to the cognitive variables, 13.1% to the WIF December intercept, and 34.8% was shared. All five predictors were statistically significant. The same four cognitive variables with the May (rather than December) WIF intercept produced a model that explained 62.1% of the variance. Of this amount, the cognitive variables and May WIF intercept accounted for 34.5% and 27.7%, respectively; they shared 37.8%. All predictors in this model were statistically significant except RAN. Logistic regression analyses indicated that the accuracy with which the cognitive variables predicted end-of-fifth-grade RD status was 73.9%. The May WIF intercept contributed reliably to this prediction; the December WIF intercept did not. Results are discussed in terms of a role for cognitive abilities in identifying, classifying, and instructing students with severe reading problems.     

Numerical investigation of penetration performance of non-ideal segmented-rod projectiles

The design of a segmented-rod projectile is often simplified into an ideal one in theoretical analysis for the convenience of modeling of its performance. But the actual performance of non-ideal segmented-rod projectiles over the impact velocity range in practical applications was rarely explored. AUTODYN numerical code is used to investigate the influence of the component design upon the penetration performance of non-ideal segmented-rod projectiles over a wide range of impact velocities, which can be used to guide the optimal design of weaponry segmented-rod projectiles.