The authors present a method that ensures control over the Type I error rate for those who visually analyze the data from response-guided multiple-baseline designs. The method can be seen as a modification of visual analysis methods to incorporate a mechanism to control Type I errors or as a modification of randomization test methods to allow…

Each of the four classic multivariate analysis of variance (MANOVA) tests of statistical significance may lead a researcher to different decisions as to whether a null hypothesis should be rejected: (1) Wilks' lambda; (2) Lawley-Hotelling trace criterion; (3) Roy's greatest characteristic root criterion; and (4) Pillai's trace criterion. These…

In the educational research literature alpha, the a priori level of significance, and p, the a posteriori probability of obtaining a test statistic of at least a certain value when the null hypothesis is true, are often confused. Explanations for this confusion are offered. Paradoxically, alpha retains a prominent place in textbook discussions of…

This paper provides researchers with a method of determining sample size for a given power level in the preparation of a single group exploratory repeated measure analysis. The rationale for determining sample size which takes into consideration the powers and assumptions of both the adjusted univariate and multivariate repeated measures tests is…

The mixed model analysis of variance assumes a mathematical property known as sphericity. Several preliminary tests have been proposed to detect departures from the sphericity assumption. The logic of the preliminary testing procedure is to conduct the mixed model analysis of variance if the preliminary test suggests that the sphericity assumption…

A growing controversy surrounds the strict interpretation of statistical significance tests in social research. Statistical significance tests fail in particular to provide estimates for the stability of research results. Methods that do provide such estimates are known as invariance or cross-validation procedures. Invariance analysis is largely…

Discusses the satisfaction of participants with videoconferencing when improved eye contact is incorporated into a system design. The Gazecam system is described, a study of 60 undergraduate students using the system is reported, and the need for communication researchers' involvement in the design process is considered. (Author/LRW)

A statistical method has been developed for nested incomplete samples in a longitudinal study in which part of the sample has dropped out in such a way that the data have a nested pattern. A procedure which performed well in a Monte Carlo experiment was extended to a two-factor incomplete design with repeated measures on one factor. Methods…

The purpose of this study was to evaluate the quality of experimental research in counseling and counselor education published from 1976 through 1984. The focus of the study was the methodology and reporting of the research rather than its relevance. Time was the independent variable of interest and three 3-year spans were chosen for examination:…

Discussion of variables that affect successful completion of external degree programs focuses on a study that investigated the association between learning style and persistence among students from the University of Wisconsin System Extended Degree Programs. Literature on distance education is reviewed, and results of the study are analyzed. (35…

This paper reports the results of a Monte Carlo investigation of Type I errors in the single group repeated measures design where multiple measures are collected from each observational unit at each measurement occasion. The Type I error of three multivariate tests were examined. These were the doubly multivariate F test, the multivariate mixed…

This study was conducted to determine whether the filmic coding elements of split screen, slow motion, generated line cues, the zoom of a camera, and rotation could aid in the development of the Euclidean space concepts of horizontality and verticality, and to explore presence and development of spatial skills involving these two concepts in…

A study was carried out at Pennsylvania State University to examine the effects of both textual and computer animated orienting activities--i.e., mediators through which new information is presented to the learner--and practice on the application and problem solving skills of elementary school students. It was hypothesized that students provided…

The Memphis Apple Classroom of Tomorrow (ACOT), one of seven ACOT locations, was a joint project of the city schools and Apple Computer. The ACOT consisted of a class of 30 fifth grade students in an inner city school, who were selected on the basis of the willingness of the students and their parents to participate and to use computers in the…

This study investigated seven methods for analyzing multivariate group differences. Bonferroni t statistics, multivariate analysis of variance (MANOVA) followed by analysis of variance (ANOVA), and five other methods were studied using Monte Carlo methods. Methods were compared with respect to (1) experimentwise error rate; (2) power; (3) number…