This Monte-Carlo study compared modified Newton (NW), expectation-maximization algorithm (EM), and minimum Cramer-von Mises distance (MD), used to estimate parameters of univariate mixtures of two components. Data sets were fixed at size 160 and manipulated by mean separation, variance ratio, component proportion, and non-normality. Results…

This paper addresses the problem of whether two-dimensional solutions with different apparent meanings and different implied interpretations of the number-correct scale could be produced from the same test data set by simply shifting the orientation of the two-dimensional projection plane. An artificial data set of 3,000 response vectors and a…

This study was designed to look for patterns of parental behavior by assessing styles of child rearing in a novel way--through responses on an interactive computer program simulating an average day in the life of a mother and a preschooler. Presented to each subject (39 mothers of preschoolers and a control group of non-mothers) were 30 common…

Complex decision-making environments often demand that a range of alternative strategies be identified and compared for their shared value in achieving desired ends. Simple parametric statistical procedures such as analysis of variance and discriminant function analysis can be used in such situations to compare (using selected criteria) the value…

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…

Results of a study to determine the effects of conceptual versus specific (traditional) training techniques on the trouble-shooting performance of maintenance technicians are presented. The research subjects were students at Bowling Green State University and citizens in Northwest Ohio with no post high school technical coursework. Those that…

This paper will discuss the results of a series of computer simulations comparing the Rasch logistic model to a series of models departing to various degrees from its assumption of equal discrimination power for all items. The results have implications for test construction and test scoring, indicating how closely the conventional raw score…

Because of limited access to technical systems used to train men to maintain complex electronic equipment, an instructional format employing low-cost slides and photos was used to provide students with simulated experiences. Five experimental instructional blocks were developed and tested in two classrooms. Results were compared with two control…

This study compares multiple person jury verdicts based on video tapes with individual decisions based on written trial accounts. An actual civil court case was used to make both the simulated video and written versions as authentic as the original trial. Adultvolunteers from the general public and college students provided the jurors. Results…

This study assessed whether slides of lighting arrangements could adequately simulate results from real space. Data indicated that in many important respects the results for the slides matched those for the real space for ratings on semantic differential scales, but that less consistent results were obtained for multidimensional scaling.…

There is evidence that students who are given information about how they appear to weigh information in reaching a judgment can learn to make judgments more accurately. A microcomputer system was used to generate simulated cases and then calculate the relationship between the data presented and the student's diagnosis. (Author/MLW)

A method of teaching alternative dispute resolution (ADR) involves sending students to observe actual ADR sessions, by agreement with the agencies conducting them, and then analyzing the students' observations in focused discussions to improve student insight and understanding of the processes involved. (MSE)

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)

A logistic regression model for characterizing differential item functioning (DIF) between two groups is presented. A distinction is drawn between uniform and nonuniform DIF in terms of model parameters. A statistic for testing the hypotheses of no DIF is developed, and simulation studies compare it with the Mantel-Haenszel procedure. (Author/TJH)

This study showed that the Elementary Perceiver and Memorizer (EPAM) can explain letter recognition phenomena earlier simulated by the connectionist Interactive Activation Model of word perception. EAPM, a model of learning and recognition in the form of a computer program, has previously explained many aspects of learning and perception. (TJH)