In a more consistent and viable manner than ever before, education in Alabama is moving toward its ultimate goal of providing every student with a quality education, thereby preparing them for work, college, and life after high school. Alabama's graduation rates from 2002 to 2008 increased significantly, tripling the national average increase and…

Booming economic prosperity, the restoration of sociopolitical stability, and the rise of disability rights have given Asian countries both impetus and resources to improve quality of life among their citizens with disabilities. This article provides an overview of rehabilitation services and training pertaining to (a) rehabilitation-related laws…

We develop a simple model of teacher behavior that offers a solution to the ''class size puzzle'' and is useful for analyzing the potential effects of the No Child Left Behind Act. When teachers must allocate limited classroom time between multiple instructional methods, rational teachers may respond to reductions in class size by reallocating…

The logic and uses of test equating are discussed, including three methods of test equating. The focus is on the conceptual underpinnings of each test equating method, rather than on the mathematics of the procedures. Additional consideration is given to the assumptions of each method and its respective strengths and weaknesses. A commonly…

Sampling error refers to variability that is unique to the sample. If the sample is the entire population, then there is no sampling error. A related point is that sampling error is a function of sample size, as a hypothetical example illustrates. As the sample statistics more and more closely approximate the population parameters, the sampling…

A new and unified approach to test equating is described that is based on log-linear models for smoothing score distributions and on the kernel method of nonparametric density estimation. The new method contains both linear and standard equipercentile methods as special cases and can handle several important equating data collection designs. An…

Central limit theorem (CLT) is considered an important topic in statistics, because it serves as the basis for subsequent learning in other crucial concepts such as hypothesis testing and power analysis. There is an increasing popularity in using dynamic computer software for illustrating CLT. Graphical displays do not necessarily clear up…

This paper explains the underlying assumptions of the sampling distribution and its role in significance testing. To compute statistical significance, estimates of population parameters must be obtained so that only one sampling distribution is defined. A sampling distribution is the underlying distribution of a statistic. Sampling distributions…

Previous research examining the effects of reducing the number of score groups used in the matching criterion of the Mantel-Haenszel procedure, when screening for differential item functioning, has produced ambiguous results. The goal of this study was to resolve the ambiguity by examining the problem with a simulated data set. The main results…

The assumption of normality underlies much of the standard statistical methodology. Knowing how to determine whether a sample of measurements is from a normally distributed population is crucial both in the development of statistical theory and in practice. W. Ware and J. Ferron have developed a new test statistic, modeled after the K-squared test…

This paper discusses the issue of multiple testing and overall Type I error rates in contexts other than multiple comparisons of means. It demonstrates, using a 5 x 5 correlation matrix, the application of 5 recently developed modified Bonferroni procedures developed by the following authors: (1) Y. Hochberg (1988); (2) B. S. Holland and M. D.…

In many large-scale educational assessments it is of interest to compare the distribution of latent abilities of different subpopulations, and track these distributions over time to monitor educational progress. B. Junker, together with two colleagues, has developed a simple scheme, based on the proportion correct score, for smoothly approximating…

This study is an attempt to answer the following research question: can the reliability of a criterion-referenced test be accurately determined according to a multiple classification of the student's performance? Specifically, the study pursues the beta-multinomial model, which postulates the probability distribution of an examinee's degree of…

Resource room students (N=68) in grades 1-7 of three rural and suburban Minnesota school districts participated in a study of time series data generated by a curriculum-based measurement system. A principal components factor analysis was performed to summarize relationships among the time-series properties and properties of the measurement system.…

The use of U-statistics based on rank correlation coefficients in estimating the strength of concordance among a group of rankers is examined for cases where the null hypothesis of random rankings is not tenable. (Author/BW)