Origin and Truth: Young Children's Understanding of Imaginary Mental Representations

In 2 studies, we address young children's understanding of the origin and representational relations of imagination, a fictional mental state, and contrast this with their understanding of knowledge, an epistemic mental state. In the first study, 54 3- and 4-year-old children received 2 tasks to assess their understanding of origins, and 4 stories to assess their understanding of representational relations. Children of both ages understood that, whereas perception is necessary for knowledge, it is irrelevant for imagination. Results for children's understanding of representational relations revealed intriguing developmental differences. Although children understood that knowledge represents reality more truthfully than imagination, 3-year-olds often claimed that imagination reflected reality. The second study provided additional evidence that younger 3-year-olds judge that imaginary representations truthfully reflect reality. We propose that children's responses indicate an early understanding of the distinction between mental states and the world, but also a confusion regarding the extent to which mental contents represent the physical world.     

Wavelet-based deconvolution of ultrasonic signals in nondestructive evaluation

INTRODUCTION Deconvolution of ultrasonic signals is defined as the solution of the inverse problem of convolving an input signal, known as the system function h(n), with a medium reflectivity function x(n) and can be rep- resented by y(n)=h(n)*x(n) η(n), (1) where y(n) is the measured signal, * denotes the convolution operation and η(n) is the additive noise. Recovering x(n) from the observation y(n) leads to improving the appearance and the axial resolution of the RF-signals by removin…     

Video Telecommunications for distance education: A field survey of systems in US public education,industry and the military

A field survey was conducted of a representative sample of 13 US educational video telecommunications (VTC) sites in public education, industry, and the military. The majority of educational/training networks use one‐way video with two‐way audio, although the use of two‐way video is increasing. Some systems regularly establish communication with others as ‘open networks’, and others are closed systems. There appears to be a trend for VTC systems to expand in the form of VTC consortia. Poor quality audio is a problem shared by many VTC systems.     

Strategies reported used by instructors to address student alternate conceptions in chemical equilibrium

This study explores general‐chemistry instructors' awareness of and ability to identify and address common student learning obstacles in chemical equilibrium. Reported instructor strategies directed at remediating student alternate conceptions were investigated and compared with successful, literature‐based conceptual change methods. Fifty‐two volunteer general chemistry instructors from 50 U.S. colleges and universities completed an interactive web‐based instrument consisting of open‐ended questions, a rating scale, classroom scenarios, and a demographic form. Survey respondents who provided responses or described remediation strategies requiring further clarification were identified (n = 6); these respondents amplified their views in separate, researcher‐led semistructured phone interviews. All 52 responding chemistry instructors reported and identified common student areas of difficulty in chemical equilibrium. They reported employing a variety of strategies to address and attempt to remediate students' alternate conceptions; however, these self‐reported strategies rarely included all four necessary conditions specified by Posner, Strike, Hewson, and Gertzog (Science Education, 66, 211–217, 1982) to stimulate conceptual change. Instructor‐identified student alternate conceptions were congruent with literature‐reported alternate conceptions of chemical equilibrium, thus providing validation support for these compilations. Implications for teaching and further research are also highlighted. © 2005 Wiley Periodicals, Inc. J Res Sci Teach 42: 1112–1134, 2005     

Developmental risk factors for sexual offending

OBJECTIVE: The aim of the study was to identify the general, common, and specific developmental risk factors for pedophilia, exhibitionism, rape, and multiple paraphilia, and to address five methodological issues observed in this area of research. METHOD: This study involved 64 sex offenders and 33 nonsex, nondrug-related, and nonviolent property offenders. The group of 64 sex offenders was further divided into eight subgroups, some of which overlapped in memberships because of multiple diagnoses. To overcome the methodological problem associated with overlapping group memberships, a special approach involving comparisons of sets of logistic regression analyses was adopted. Offenders were clinically assessed for evidence of paraphilias, and their adverse childhood experiences were measured by a battery of tests. RESULTS: Childhood Emotional Abuse and Family Dysfunction, Childhood Behavior Problems, and Childhood Sexual Abuse were found to be general developmental risk factors for paraphilias. Furthermore, Childhood Emotional Abuse and Family Dysfunction was found to be a common developmental risk factor for pedophilia, exhibitionism, rape, or multiple paraphilia. Additional analyses revealed that childhood emotional abuse contributed significantly as a common developmental risk factor compared to family dysfunction. Besides, Childhood Sexual Abuse was found to be a specific developmental risk factor for pedophilia. CONCLUSIONS: The study has supported the value of conceptualizing certain childhood adversities as developmental risk factors for paraphilic behaviors. The role of childhood emotional abuse as an important developmental risk contributor, and the relationship between childhood sexual abuse and pedophilia are of theoretical significance. Furthermore, the results have significant implications for the prevention of childhood abuse and treatment of sex offenders.     

Why and How Parents Promote Math Learning with their Young Children: A Mixed-Methods Investigation

SYNOPSIS

Objective. This study examined parental characteristics that related to children’s early math learning. Specifically, we examined how parents engage in math activities with their children in the home and how their practices were informed by parents’ experiences with and perceptions of math. Design. Using a mixed-methods design, we first quantitatively examined associations between two parental characteristics, past math experiences and current math anxiety, and various types of math activities to understand factors that predict home math engagement in a sample of 34 parents. We then conducted semi-structured interviews with a sample of 15 parents to identify additional factors that relate to parents’ engagement in math activities with their young children. Results. We found that parents’ math anxiety predicted their reports of math activity frequency in the home, controlling for demographics as well as prior measures of math enrichment. Through qualitative analyses, we demonstrated considerable variability in the way that math activities are implemented and described by parents and identify a novel theoretical construct – parents’ goals for children’s math learning – which relates to parents’ practices. Conclusions. These results suggest that survey measures may fail to capture important heterogeneity in parents’ practices and that additional predictors such as parental goals should be explored in future quantitative research.     

An example based environment for beginning programmers

Making a good programming environment for beginning programmers is an enterprise which can exploit the strong connections between machine learning and human learning. Applying what we know about teaching and learning to improve the programming environment can result in a system which allows beginners to more readily acquire programming skills.Surprisingly, a universally accepted principle of good teaching and good learning has not been taken seriously enough in designing programming environments-learning by example. A good teacher presents examples of how to solve problems, and points out what is important about the examples. The student generalizes from the examples to learn principles and techniques. This paper describes a programming environment called Tinker, in which a beginning programmer presents examples to the machine, distinguishing accidental and essential aspects of the examples. The programmer demonstrates how to handle the specific examples, and the machine formulates a procedure for handling the general case. Because people are much better at thinking about concrete examples than they are at thinking about abstractions, and because examples provide immediate feedback, Tinker is a more congenial environment for a beginner than conventional programming systems.     

Advanced project work in distance teaching

The problem of presenting advanced project work in distance teaching is discussed and criteria established for its success. An evaluation of empirical research projects involved in an advanced course on research methods in education and social science is described and some principles put forward for sound project design in distance teaching. Finally, three models suggesting different combinations of distance teaching and conventional institution-based teaching are proposed which incorporate advanced project work. It is suggested that conventional teaching institutions working in isolation can all benefit from a distance teaching element in their programmes.