Data collected from surveys can result in hundreds of variables and thousands of respondents. This implies that time and energy must be devoted to (a) carefully entering the data into a database, (b) running preliminary analyses to identify any problems (e.g., missing data, potential outliers), (c) checking the reliability and validity of the…

Specific language impairment (SLI) comprises impairments in receptive and/or expressive language. Aim of this study was to evaluate a screening for SLI. 61 children with SLI (SLI-children, age-range 4-6 years) and 61 matched typically developing controls were tested for receptive language ability (Token Test-TT) and for intelligence (Wechsler…

If the null hypothesis of a one-sample test of multivariate means is rejected, the dimension of the line joining the population centroid and the hypothesized centroid can be interpreted with a linear function, using a discriminant function and the correlation of each dependent variable with a discriminant score. (Author/BW)

A method of applying the discriminant function to correlated samples was discussed for the researcher interested in utilizing multivariate statistics to pre-post data. By finding the linear combination that maximizes differences in the groups, the t-statistic can be computed for correlated samples. (Author)

Suppose P to the subpower of 1 and P to the subpower of 2 are two competing discrimination procedures. To compare the relative discriminatory power of both procedures, test statistics are suggested for the hypothesis that P to the subpower of 1 and P to the subpower of 2 performed no better than random assignment versus the alternative that P to…

Empirical studies addressing admission to and graduation from a doctoral program focusing on educational leadership are noticeably absent within the professional literature, and this study seeks to fill partially this void through testing specific hypotheses. Archival data were used to conduct a three group discriminant analyses where the…

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…

Evaluations involving nonrandom assignment to treatment or control groups are vulnerable to an accidental or intentional confounding of a selection effect with the treatment effect. Two techniques, discriminant analysis and base expectancy analysis, permit separate estimation of the selection and treatment effects in the final results. (Author/CTM)

GREATER UNDERSTANDING OF INFERENTIAL STATISTICAL METHODS AND EXPERIMENTAL DESIGN WOULD ENABLE LANGUAGE TEACHERS TO INTERPRET OBJECTIVELY AVAILABLE RESEARCH REPORTS AND HOPEFULLY WOULD ENCOURAGE MORE EXPERIMENTATION. TO UNDERSTAND THE EXPERIMENTAL PROCESS, EDUCATORS MUST REALIZE THAT ANY EXPERIMENT IS AS SUCCESSFUL AS THE EXPERIMENTER IS IN…

The power of the classical Linear Discriminant Function (LDF) is compared, using Monte Carlo techniques with five other procedures for classifying observations from certain non-normal distributions. The alternative procedures considered are the Quadratic Discriminant Function, a Nearest Neighbor Procedure with Probability Blocks, and three density…

This paper relates educational and psychological statistics to certain "Research Statistical Tools" (RSTs) necessary to accomplish and understand general research in the behavioral sciences. Emphasis is placed on acquiring an effective understanding of the RSTs and to this end they are are ordered to a continuum scale in terms of individual…

The VARAN (variance Analysis) program is an addition to a series of computer programs for multivariate analysis of variance. The development of VARAN exploits the full linear model. Analysis of variance, univariate and multivariate, is the program's main target. Correlation analysis of all types is available with printout in the vernacular of…

Research is a useful tool for educators because of its ability to uncover causal relationships between variables that are often obscured in field investigations. This textbook presents basic methodological information that has been designed for and proven to assist the educator who seeks to move himself from the laboratory to the field. The book…