When estimating causal effects from observational data, it is desirable to approximate a randomized experiment as closely as possible. This goal can often be achieved by choosing a subsample from the original control group that matches the treatment group on the distribution of the observed covariates. However, sometimes the original control group…

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…

A recent U.S. Department of Education (2009) meta-analysis concluded that blended learning may be better than either online or traditional lecture-based instruction. However, other research has shown that, for technology-enhanced instruction, learning outcomes are, at best, equal to traditional lecture-based instruction. Blended learning, when…

Many of today's colleges and universities are venturing into online education, with distance education enrollments in the United States having increased from 1.6 million students in 1998 to over 3.9 million in 2007. However, concerns over student frustrations and high attrition rates in online learning have led many educators to research and…

Augmented Reality (AR) simulations superimpose a virtual overlay of data and interactions onto a real-world context. The simulation engine at the heart of this technology is built to afford elements of game play that support explorations and learning in students' natural context--their own community and surroundings. In one of the more recent…

Substantial evidence now supports pedagogical applications of virtual worlds; however, most research supporting virtual worlds for education has been conducted using researcher-developed Multi-User Virtual Environments (MUVE). Second Life (SL) is a MUVE that has been adopted by a large number of academic institutions; however, little research has…

Medical education institutions frequently simulate interactions between future health professionals and standardized patients. This manuscript describes a partnership between a teacher preparation institution and a nearby medical institution, outlining specific procedures associated with the use of standardized parents, students, and…

Traditionally, at least according to popular wisdom, learning took place in venues that were custom-designed for the purpose. The purpose, given the evidence of the artefacts with which we are confronted, seems to have been the educational equivalent of the production line that so succinctly characterised the industrialisation of society. One…