This paper presents a model which illustrates the cyclical and interactive nature of the basic elements of the research design process. Rather than presenting each research design component in isolation, the model emphasizes their interrelationships. A brief discussion is presented on each of the following components of the model: (1) the "words"…

The purpose of this paper is to demonstrate the use of the general linear model (GLM) in problems with repeated measures on a dependent variable. Such problems include pretest-posttest designs, multitrial designs, and groups by trials designs. For each of these designs, a GLM analysis is demonstrated wherein full models are formed and restrictions…

If they are to develop more effective social intervention strategies, social scientists must pay attention to social causality in their research. This will lead to more credibility for the social sciences and more support for research funds. Social causality is defined as a social process that produces a change in some dependent variable. It…

The value of variance is emphasized, and the element of design, frequently not adequately understood, is clarified to underscore the importance of variance to the researcher. Two analytic methods, analysis of variance (ANOVA) and multiple regression, are discussed in terms of how each uses/applies variance. Advantages and major difficulties with…

The purpose of the School Improvement Model (SIM) Project is to investigate the links between systematically developed teacher performance evaluation, administrator performance evaluation, staff development interventions, and the quality of education as measured by student achievement results. Following the 4th year of the 5-year study,…

Since research indicates that young children influence their mothers and that mothers may exert indirect influences on their children's language learning, this correlational, longitudinal study was conducted to identify indirect routes through which early maternal speech was related to later child language development. Participants were 10…

New ways of using factor analysis in research designs are suggested in this paper that would allow research to move in new directions that are being suggested for educational technology. A brief simplified overview of factor-analytic techniques is given, followed by a description of some recent developments in factor-analytic techniques which make…

The stepwise regression method of selecting predictors for computer assisted multiple regression analysis was compared with forward, backward, and best subsets regression, using 16 data sets. The results indicated the stepwise method was preferred because of its practical nature, when the models chosen by different selection methods were similar…

Levels of independent variable(s) are often mixed within each block of trials rather than each level being presented in a separate block in research of various types. Two experiments involving tasks of a visual nature were conducted to demonstrate that such mixing can easily obscure the effects of principal interest. A target circle was projected…

The Mahalanobis distance model was compared with the linear discriminant function model and found to provide very similar results, even when a number of the variables were binary. A group of college freshmen were categorized into two groups: 116 "leavers," students who did not return for the second year, and 269 "returners."…

Methods for ordering and selecting variables for discriminant analysis in multiple group comparison or group prediction studies include: univariate Fs, stepwise analysis, learning discriminant function (LDF) variable correlations, communalities, LDF standardized coefficients, and weighted standardized coefficients. Five indices based on distance,…

The concept of quality is analyzed with special attention to its different senses in two contexts: qualitative evaluation and assessment of educational program quality. The view that evaluation of program quality cannot be validly expressed in quantitative terms and that qualitative evaluation methodologies have special relevance for the…

Building communication theory in terms of three-variable relationships is a promising route to developing better theory, because three-variable relationships stand midway between sometimes overly simplistic two-variable relationships, and the more complex path analysis. The analysis of three-variable relationships has been done in many previous…

Three procedures used to control Type I error rate in stepwise regression analysis are forward selection, backward elimination, and true stepwise. In the forward selection method, a model of the dependent variable is formed by choosing the single best predictor; then the second predictor which makes the strongest contribution to the prediction of…

Arguments have recently been put forth that standard textbook procedures for determining the sample size necessary to achieve a certain level of power in a completely randomized design are incorrect when the dependent variable is fallible because they ignore measurement error. In fact, however, there are several correct procedures, one of which is…