The examination of measurement invariance in polytomous items is complicated by the possibility that the magnitude and sign of lack of invariance may vary across the steps underlying the set of polytomous response options, a concept referred to as differential step functioning (DSF). This article describes three classes of nonparametric DSF effect…

Equating functions are supposed to be population invariant, meaning that the choice of subpopulation used to compute the equating function should not matter. The extent to which equating functions are population invariant is typically assessed in terms of practical difference criteria that do not account for equating functions' sampling…

Recent work addressing the phenomenon of perceptual simulation offers new and exciting avenues of investigating how to model knowledge representation. From the perspective of language, the simulation approach has given rise to new impetus to work on models of language understanding (e.g., Zwaan, 2004, and references therein), and provides a way of…

There has been a body of emerging research describing students' understanding of complex systems. This research has primarily studied students understanding of complex phenomena in science. However, complex phenomena are also pervasive in everyday life. Children observe and participate in them daily. How do they reason about such ordinary complex…

Asperger's patients have been treated by role-playing with real-life therapists. The virtual-reality town at the medical center is a new twist. The University of Texas at Dallas uses a platform from Second Life, the popular virtual world, in which patients go to an "island" customized for therapeutic purposes. The island was built by…

To create an environment in which all students have opportunities to notice, describe, and wonder about variability, this article takes a context familiar to many teacher--sampling colored chips from a jar--and shows how this context was used to explicitly focus on variation in the classroom. The sampling activity includes physical as well as…

A primary criterion on which models of cognition are evaluated is their ability to fit empirical data. To understand the reason why a model yields a good or poor fit, it is necessary to determine the data-fitting potential (i.e., flexibility) of the model. In the first part of this article, methods for comparing models and studying their…

Changes to research methodology motivated by the adoption of a complexity theory perspective on language development are considered. The dynamic, nonlinear, and open nature of complex systems, together with their tendency toward self-organization and interaction across levels and timescales, requires changes in traditional views of the functions…

Virtual Reality (VR) is a creation of virtual 3D world in which one can feel and sense the world as if it is real. It is allowing engineers to design machines and Educationists to design AV [audiovisual] equipment in real time but in 3-dimensional hologram as if the actual material is being made and worked upon. VR allows a least-cost (energy…

The "Health Professions Education: A Bridge to Quality" (IOM, 2003) proposed strategies for higher education leaders and faculty to transform their institutions in ways that address the healthcare problems. This study provides higher education leaders and faculty with empirical data about the processes of change involved to implement the…

Computer advances now let researchers quickly search through DNA sequences to find gene variations that could lead to disease, simulate how flu might spread through one's school, and design three-dimensional animations of molecules that rival any video game. By teaming computers and biology, scientists can answer new and old questions that could…

Product life cycle (PLC) stages and diagrams are briefly and dispassionately covered in the standard marketing textbook format with little attention to the social-psychological experiences of those actually participating. This qualitative study used process drama as a teaching tool and a research instrument to probe the PLC phenomenon in a…

Doctoral education in the United States had been scrutinized because of high-attrition rates reported as an average of 50 percent. Emerging from Lovitts (2001), this research examined students' attendance at Mock Orals (MO) and its relationship to their academic and social integration, cognitive maps, goals, rates of attrition, and retention in a…

The purpose of this study was to investigate how modeling-based instruction combined with an interactive-engagement teaching approach promotes students' problem solving abilities. I focused on students in a calculus-based introductory physics course, based on the matter and interactions curriculum of Chabay & Sherwood (2002) at a large state…

Exploratory factor analysis (EFA) is generally regarded as a technique for large sample sizes ("N"), with N = 50 as a reasonable absolute minimum. This study offers a comprehensive overview of the conditions in which EFA can yield good quality results for "N" below 50. Simulations were carried out to estimate the minimum required "N" for different…