Metacognition as a Basis for Learning Support Software

In order to understand the task of instructional designers who produce learning support software, this paper reviews the influence of learning theory on instructional design, recent developments in computer technology, and the evolving role of the instructor as a facilitator of higher-order thinking. Constructivist principles of learning and an appreciation for the fact that the learner must become more independent and skilled in metacognitive self-assessment and self-management are fundamental to this changing role. Two cognitive tools that provide learner/user support for personal construction of knowledge systems are “MindMap” and “Learning FourMat Processor.” These tools are examined in the light of current learning theory and a recent study comparing the work of novice and expert writers using different forms of performance support. Recommendations are made for the development of a more complete set of cognitive tools that enables users to construct their own multimedia knowledge systems based on higher-order thinking and problem solving.     

Detecting potential hucksterism in meta-analysis using a follow-up fail-safe test

Meta-analysis is an analysis of analyses. It is a technique widely used by researchers and practitioners to aggregate and summarize statistically reported empirical educational research. In 10 years, meta-analysis appeared more than 600 times in research journals and dissertation abstracts. Although most meta-analyses were reported as significant, few of the findings determined how many unpublished “no-effect” studies, if sampled, would have invalidated significance. If significant meta-analysis results are over represented through selective sampling, hucksterism in the form of sampling bias exists. An explanation for using a follow-up test called the fail-safe N is provided with tables constructed to assist researchers and practitioners to estimate, without calculation, the relative stability of meta-analysis results. The implication is that failsafe N should routinely be used and reported in meta-analysis research.     

The retrograde motion of planets and children: Interpreting percentile rank

A common method used to interpret raw scores is to convert them into percentile rank. The broad application of percentile rank in almost all norm-referenced tests, and the exclusive use in some tests, requires the conversion of raw scores. Because percentile rank is not a linear transformation of raw scores, percentile-rank transformation in the lower and upper part of the raw-score distribution relates percentile rank and raw scores differently than in the center of the raw-score distribution. This paper describes the popularity of using percentile rank and offers an interpretation of the use of percentile rank with normal and skewed score distributions.     

Variable uses of alternative conceptions: A case study in current electricity

Recent research related to the design of science instruction is often based on conceptual change theory and requires assessments of what knowledge students bring to instruction. The premise of this study was that it is also important to understand when and how students apply their knowledge. Fourteen elementary and middle school teachers in an in-service physics course were asked to solve qualitatively a variety of series and parallel circuit problems and explicate their reasoning. These teachers were found to share a common core of strongly held propositions that formed a coherent, but incorrect and contradictory model of sequential current flow. Yet their predictions about the circuits were highly variable. The variability in predictions resulted from differences and contradictions in additional “protective belts” of propositions, and differences in the ways in which the teachers changed and selectively applied those propositions to different problems. Understanding the variations in not only what teachers knew, but also the differences in when and how they applied their knowledge complicated the task of designing instruction. However, it also made possible the design of more precise instruction in which the teachers were required to recognize, confront, and reconcile specific inconsistencies in their beliefs.     

Color characterization of roofing slates from the Iberian Peninsula for restoration purposes

Substitution of slate roofing tiles is a conventional operation during building restoration, since tiles are very difficult to restore or clean because of the high degree of alteration they suffer. Criteria for replacement of historical building stones must be based on geological, geotechnical and esthetic parameters, among which color is of great importance. In this sense, this paper constitutes a comprehensive and useful colorimetric study of roofing slates from the Iberian Peninsula, for the purposes of restoration. The color of 50 commercial varieties of roofing slate mined in quarries from the 12 mining districts in the Iberian Peninsula was analyzed with a spectrophotometer device, by considering the CIELAB color space. The results of the study were used to develop a protocol for characterizing the color of roofing slate and to define the color range of roofing slate from the Iberian Peninsula. In addition, the similarities and differences in the color and microstructure of the different commercial varieties of Iberian roofing slate were established and the limit of acceptability of replacement of one type of slate by another was determined. Parameter h_ab was found to be the most important CIELAB color coordinate as regards the formation of homogeneous color groups, and the specular component excluded (SCE) mode was most sensitive as regards detecting color differences between two samples.