The major purpose of this evaluation report is to scrutinize the Skyline Wide Educational Plan (SWEP) research methods and analytical schemes and to communicate the project's constituency priorities relative to the educational programs and processes of the future. A Delphi technique was used as the primary mechanism for gathering and scrutinizing…

Learning hierarchies are networks of prerequisite relationships of instructional objectives. Seven measures of the validity of learning hierarchies were compared for their ability to identify correctly- and incorrectly-ordered hierarchies. A computer simulation model was used to generate stochastic data of known underlying structure. Analysis of…

A modification index is presented to aid in reformulating hypothetical models rejected after analysis of empirical data. This index is an improvement over the one in the LISREL V computer program in that it takes into account changes in all parameters of the model when one parameter is freed. (SLD)

Functional and structural relationship alternatives to the standard "F"-test for analysis of covariance (ANCOVA) are discussed for cases when the covariate is measured with error. An approximate statistical test based on the functional relationship approach is preferred on the basis of Monte Carlo simulation results. (SLD)

Type I error rate and power for the t test, Wilcoxon-Mann-Whitney test, van der Waerden Normal Scores, and Welch-Aspin-Satterthwaite (W) test are compared for two simulated independent random samples from nonnormal distributions. Conditions under which the t test and W test are best to use are discussed. (SLD)

Provides a conceptual framework for information systems (IS) that can be used in AIDS intervention and prevention (AIP). System components are analyzed, including a database, decision support systems (DSS), expert systems, and software; potential applications of ISAIP are suggested; and an example of a system implemented at Wright State University…

To deal with nonnormal and heterogeneous data for the one-way fixed effect analysis of variance model, the authors adopted a trimmed means method in conjunction with Hall's invertible transformation into a heteroscedastic test statistic (Alexander-Govern test or Welch test). The results of simulation experiments showed that the proposed technique…

Purpose: The purpose of this study was to develop guidelines for the statistical analysis of percentage of syllables stuttered (%SS) data in stuttering research. Method; Data on %SS from various independent sources were used to develop a statistical model to describe this type of data. On the basis of this model, %SS data were simulated with…

Differential item functioning (DIF) continues to receive attention both in applied and methodological studies. Because DIF can be an indicator of irrelevant variance that can influence test scores, continuing to evaluate and improve the accuracy of detection methods is an essential step in gathering score validity evidence. Methods for detecting…

Possible bias due to sampling problems or low response rates has been a troubling "nuisance" variable in empirical research since seminal and classical studies were done on these problems at the beginning of this century. Recent research suggests that: (1) earlier views of the alleged bias problem were misleading; (2) under a variety of fairly…

Simultaneous estimation of many parameters can often be improved, sometimes dramatically so, if it is reasonable to consider one or more subsets of parameters as exchangeable members of corresponding populations. While each observation may provide limited information about the parameters it is modeled directly in terms of, it also contributes…

The intent of the study was to determine the extent to which test statistics computed by the unweighted means analysis are F-distributed. Applicability criteria were sought in terms of the number of factor levels and the degree to which cell frequencies differ. The unweighted means analysis, a frequently used approximate analysis, was contrasted…

This paper deals with a study designed to pursue the question; "What treatment by whom is most effective for this individual with that specific problem under which set of circumstances?" One of the objectives of the study was to determine if there was any relationship between two predictor variables, personality type (extraversion-introversion)…

One of several studies initiated by the Economic Research Service to provide research approaches in the problem areas of rural poverty and economic development, this study examines (1) rural activities within the context of national activities, (2) regional growth theories, (3) growth forecasting, (4) developmental programing, (5) determining a…

This paper investigates three methods for comparing medians rather than means in studying two independent treatment groups. The method that gave the best results is based on a normal approximation of the distribution of the sample median where the variance is estimated using results reported by Maritz and Jarrett. (Author/JAZ)