Threedifferent statistical procedures for identifying aptitude-treatment interactions are discussed: (1) treatment x blocks analysis of variance (2) homogeneity of groups regressions and (3) extreme groups analysis. (Author)

Replication is important to viable scientific inquiry; results that will not replicate or generalize are of very limited value. Statistical significance enables the researcher to reject or not reject the null hypothesis according to the sample results obtained, but statistical significance does not indicate the probability that results will be…

Using a Monte Carlo approach, comparison was made between traditional procedures and a multiple linear regression approach to test for differences between values of r sub 1 and r sub 2 when sample data were dependent and independent. For independent sample data, results from a z-test were compared to results from using multiple linear regression.…

Determination of statistical power for analysis of variance procedures requires five elements: (1) significance level; (2) effect size; (3) number of means; (4) error variance; and (5) sample size. Significance levels are traditionally chosen to be 0.5, .01, or .001. Effect size is not discussed in this paper. The number of means is determined by…

This study examines the relative effectiveness of two means of analyzing the pre-test/post-test control group experimental design. Samples were randomly drawn from a standardized normal population and assigned to one of the four cells of the design. A set of experimental differences were induced in the post-test experimental cell. Each case was…

The high incidence of reported posttraumatic stress disorder (PTSD) among Vietnam veterans has prompted researchers to search for reliable assessment and treatment procedures for this disorder. Although some encouraging preliminary data on the use of the Minnesota Multiphasic Personality Inventory (MMPI) have been obtained, it is uncertain if this…

IN AN EXPERIMENT TO TEST EFFECTS OF A PROGRAMED TEXT AND RECORDS IN MUSIC INSTRUCTION, A PRE-TEST ON WRITTEN THEORY AND AURAL RESPONSE GIVEN TO 957 STUDENTS IN NINE SCHOOLS IN AN EXPERIMENTAL AND A MATCHED CONTROL GROUP SHOWED SIGNIFICANT DIFFERENCES FOR THOSE WITH PREVIOUS PRIVATE MUSIC STUDY AND HIGHER GRADE POINT AVERAGES, BUT NO DIFFERENCES ON…

The purpose of the present study was to investigate empirically the effects of violations of the assumption of homogeneity of within-group regression slopes on levels of significance in the F test of fixed-effects ANCOVA (analysis of covariance). The study used a Monte Carlo computer simulation procedure to generate data under the following…

When analysis of variance is used, statistically significant differences may or may not be of practical significance to educators. A large part of the problem is due to the fact that a "zero difference" null hypothesis can always be rejected statistically if the sample size is large enough. If, however, a method based on the noncentral F…

This paper presents an index of goodness-of-fit for comparing m models over n trials. The index allows for differentiated weighting of the trials as to their importance in the comparison of the models. Several possible weighting schemes are suggested and the conditions on the weights which assure asymptotic normality of the index distribution are…

This paper discusses the use of contrast coefficients in multiple linear regression models, and shows how they can provide for a logical method of analysis in both the analysis of variance and the analysis of covariance. (CK)

Texts often suggest running preliminary tests for homogeneity of variance prior to running an ANOVA. While it has been known for some time that most of the suggested tests are probably not appropriate, they are still being used. This paper is a review of the literature in terms of the implications involved in running preliminary tests in general…

Neglected issues of simultaneous statistical inference and statistical power in survey research applications of the general linear model are reviewed, and it was found that classical hypothesis testing as it is currently applied, is inadequate for the purposes of social research. The intelligent use of statistical inference demands control over…

A statistical method, Fishers Table of t (or t ratio), is used to determine the statistical significance of a comparison of results from pretests and post-tests of knowledge and skill taken by training program participants. A statistically significant improvement can demonstrate training effectiveness. (MS)

Kaufman and Sweet's article on the regression analysis of unbalanced factorial designs (EJ 111 767) is reviewed. A number of errors are noted, and relevant literature is cited. (GDC)