Unlike their monotone counterparts, nonparametric unfolding response models, which assume the item response function is unimodal, have seen little attention in the psychometric literature. This paper studies the nonparametric behavior of unfolding models by building on the work of Post (1992). The paper provides rigorous justification for a class…

Illness and injuries are common among students and school staff. Therefore, school nurses must be prepared. In this study, a 16-hour scenario-based emergency preparedness course for school nurses was evaluated for its effectiveness. Effectiveness was measured by (a) traditional methods (written exams and confidence surveys) and (b) skills and…

This article presents an interview with Clark Aldrich, whose expertise as an "e-learning guru" (one of three identified by "Fortune" magazine in November 2000) rests on substantial foundations: his service as the Gartner Group research director who initiated and developed the firm's e-learning coverage, his leadership of the world class team that…

The instructional scheduling arrangements of simulated and community-based instruction across an equivalent set of functional and vocational skills were examined. Five secondary age students with moderate intellectual disabilities participated in four instructional scheduling arrangements measuring skill acquisition, generalization, and…

This paper reports a set of Monte Carlo simulations designed to evaluate the main claims made by Laufer and Nation about the Lexical Frequency Profile (LFP). Laufer and Nation claim that the LFP is a sensitive and reliable tool for assessing productive vocabulary in L2 speakers, and they suggest it might have a serious role to play in diagnostic…

Building and launching model rockets makes a great activity for a technology education class. A model rocket curriculum provides a valuable tool for improving students' technical skills that includes, but is not limited to, following technical instructions and procedures while learning about aerospace technology. This article describes a way that…

When the underlying responses are on an ordinal scale, gamma is one of the most frequently used indices to measure the strength of association between two ordered variables. However, except for a brief mention on the use of the traditional interval estimator based on Wald's statistic, discussion of interval estimation of the gamma is limited.…

The regression trunk approach (RTA) is an integration of regression trees and multiple linear regression analysis. In this paper RTA is used to discover treatment covariate interactions, in the regression of one continuous variable on a treatment variable with "multiple" covariates. The performance of RTA is compared to the classical…

Weekly cycles in emotion were examined by combining item response modeling and spectral analysis approaches in an analysis of 179 college students' reports of daily emotions experienced over 7 weeks. We addressed the measurement of emotion using an item response model. Spectral analysis and multilevel sinusoidal models were used to identify…

In the context of item response theory, it is not uncommon that person-by-item data are correlated beyond the correlation that is captured by the model--in other words, there is extra binomial variation. Heterogeneity of the parameters can explain this variation. There is a need for proper statistical methods to indicate possible extra…

In their reply to our article, Greenwald, Rudman, Nosek, and Zayas offered comments on the use of their procedure relative to one that focuses on standard multiple regression (SMR) methods). Here we address five issues where we think a balance of perspective is called for: (a) issues of measurement, (b) the structuring and reporting of the…

This study compared vertical scaling results for the Rasch model from BILOG-MG and WINSTEPS. The item and ability parameters for the simulated vocabulary tests were scaled across 11 grades; kindergarten through 10th. Data were based on real data and were simulated under normal and skewed distribution assumptions. WINSTEPS and BILOG-MG were each…

We conceptualize personality and individual variation from the perspective of dynamical systems. People's thoughts, feelings, and predispositions for action are inherently dynamic, displaying constant change due to internal mechanisms and external forces, but over time the flow of thought and action converges on a narrow range of states--a…

During locomotion, retinal flow, gaze angle, and vestibular information can contribute to one's perception of self-motion. Their respective roles were investigated during active steering: Retinal flow and gaze angle were biased by altering the visual information during computer-simulated locomotion, and vestibular information was controlled…

The approach taken in the present investigation was to examine reactions to positive and negative employer information by eliciting online (i.e., moment-to-moment) reactions in a simulated computer-based job fair. Reactions to positive and negative information commonly reveal a negatively biased asymmetry. Positively biased asymmetries have been…