The purpose of this study was to empirically evaluate the impact of loglinear presmoothing accuracy on equating bias and variability across chained and post-stratification equating methods, kernel and percentile-rank continuization methods, and sample sizes. The results of evaluating presmoothing on equating accuracy generally agreed with those of…

The search for cut-off criteria of fit indices for model fit evaluation (e.g., Hu & Bentler, 1999) assumes that these fit indices are sensitive to model misspecification, but not to different types of models. If fit indices were sensitive to different types of models that are misspecified to the same degree, it would be very difficult to establish…

The author considers a latent trait model for the response time on a (set of) pure speed test(s), the multiplicative gamma model (MGM), which is based on the assumption that the test response times are approximately gamma distributed, with known index parameters and scale parameters depending on subject ability and test difficulty parameters. Like…

A number of methods are available in the literature to measure confidence intervals. Here, confidence intervals for estimating the population mean of a skewed distribution are considered. This note proposes two alternative confidence intervals, namely, Median t and Mad t, which are simple adjustments to the Student's t confidence interval. In…

In this study, the authors assess several strategies created on the basis of the Mantel-Haenszel (MH) procedure for conducting differential item functioning (DIF) analysis with small samples. One of the analytical strategies is a loss function (LF) that uses empirical Bayes Mantel-Haenszel estimators, whereas the other strategies use the classical…

Virtual reality (VR) technology has demonstrated effectiveness in a variety of technical learning situations, yet little is known about its differential effects on learners with different levels of visual processing skill. This small-scale exploratory study tested VR through quasi-experimental methodology and a theoretical/conceptual framework…

A continuing challenge to the undergraduate chemical engineering curriculum is the time-effective incorporation and use of computer-based tools throughout the educational program. Computing skills in academia and industry require some proficiency in programming and effective use of software packages for solving 1) single-model, single-algorithm…

Part of the history of oil and gas development on Indian reservations concerns potential underpayment of royalties due to under-valuation of production by oil companies. This paper discusses a model used by the Shoshone and Arapaho tribes in a lawsuit against the Federal government, claiming the Government failed to collect adequate royalties.…

In a well-designed experiment, random assignment of participants to treatments makes causal inference straightforward. However, if participants are not randomized (as in observational study, quasi-experiment, or nonequivalent control-group designs), group comparisons may be biased by confounders that influence both the outcome and the alleged…

This article familiarizes readers with how to analyze personnel selection decisions in employment discrimination litigation. First, the authors outline some of the basic legal principles that serve as the basis for analyses related to claims of discriminatory employment practices. Second, they describe how to conduct a scientific investigation of…

Multiple comparison procedures for controlling familywise Type I error and the false discovery rate are described and compared, including the traditional Bonferroni correction, a sequential (step-up) Bonferroni procedure (Hochberg, 1988), and a sequential false discovery rate procedure proposed by Benjamini and Hochberg (1995). Motivation for…

Techniques for automatic recognition of isolated words are investigated, and a computer simulation of a word recognition system is effected. Considered in detail are data acquisition and digitizing, word detection, amplitude and time normalization, short-time spectral estimation including spectral windowing, spectral envelope approximation,…

This article applies the Breslow-Day test of trend in odds ratio heterogeneity (BD) to the detection of nonuniform DIF. A simulation study was conducted to assess the power and Type I error rate of BD, as well as a combined decision rule (CDR), whereby a decision of the existence of DIF was based on a combination of the decisions made using BD and…

A common mistake in analysis of cluster randomized trials is to ignore the effect of clustering and analyze the data as if each treatment group were a simple random sample. This typically leads to an overstatement of the precision of results and anticonservative conclusions about precision and statistical significance of treatment effects. This…

It has been proposed that it is possible to decompose changes in variability of human motor behavior into 3 independent components: covariation, task tolerance, and stochastic noise. The authors simulate learning to throw accurately and show that for this task the proposed analysis does not give an unambiguous answer to the question of what the 3…