School-effectiveness research is constrained by ambiguous factors of effectiveness and a lack of theory. This paper presents findings of a study that used simulation to improve school-effectiveness theory. Simulation is also used to explore the direct effects of schools on individual learning. After introducing simulation models, the paper…

The central thesis of this article is that the process of eliminating validity threats depends fundamentally on no-difference findings, a fact that has not been made explicit by researchers. The implications of this neglect are explored using examples from a number of different substantive areas such as psychology, health, and medicine.…

The focus here is on the students' uses for numbers in both school and home settings. The included activities emphasize a growth and development theme involving various aspects of data collection, data interpretation, probability, and statistics. Also included are parent-child extended activity worksheets. (JJK)

Variance formulas of H. E. Daniels and M. G. Kendall (1947) are generalized to allow for the presence of ties and variance of the sample tau correlation. Applications of these generalized formulas are discussed and illustrated using data from a 1965 study of contraceptive use in 15 developing countries. (SLD)

Discusses five common myths about statistical significance testing (SST), the possible erroneous and harmful contributions of SST to educational research, and suggested alternatives to SST for mathematics education research. (Contains 61 references.) (MKR)

Diagnostic score reports linking assessment outcomes to instructional interventions are one of the most requested features of assessment products. There is a body of interesting work done in the last 20 years including Tatsuoka's rule space method (Tatsuoka, 1983), Haertal and Wiley's binary skills model (Haertal, 1984; Haertal & Wiley, 1993),…

Three versions of a probabilistic model adapted from the theory of information retrieval--a binary version, a version using the full value of the data, and a version using principal components--were tested and applied to data available from application forms to predict graduate school performance of library school students. (EM)

This article investigates two common methods of determining the line of best fit and then expands on the techniques used in these methods to find the line of best fit by graphing, estimating and using a microcomputer. (PK)

Web-based statistical instruction, like all statistical instruction, ought to focus on teaching the essence of the research endeavor: the exercise of reflective judgment. Using the framework of the recent report of the American Psychological Association (APA) Task Force on Statistical Inference (Wilkinson and the APA Task Force on Statistical…

Two extensions of the Mantel Haenszel procedure that may be useful in assessing differential item functioning (DIF) are explored. Simulation results showed that, for both inferential procedures, the studied item should be included in the matching variable, as in the dichotomous case. (SLD)

The use of tests of statistical significance was explored, first by reviewing some criticisms of contemporary practice in the use of statistical tests as reflected in a series of articles in the "American Psychologist" and in the appointment of a "Task Force on Statistical Inference" by the American Psychological Association…

This handbook is intended to help government, university, private sector, and other users become better acquainted with the concepts and data underlying the Department of Agriculture's statistical series. The introduction reviews what various pieces of federal legislation say about the computation of agricultural production costs by the U.S.…

Presents teaching activities that are intended to be used to teach statistics to students in a high school mathematics program. Includes a worksheet of eight discussion questions on statistics, four activities on sampling bias, two experiments on sampling techniques, and a game known as "capture-recapture." (TW)

Possible relationships between five test examiner characteristics (gender, race, tenure, experience as a test administrator, and experience as a test developer or scorer) and six student achievement scores (reading, writing, language usage, mathematics, science, and social studies) were studied at the school level in a statewide assessment. The…

In this study we test the performance of some nonexperimental estimators of impacts applied to an educational intervention--reduction in class size--where achievement test scores were the outcome. We compare the nonexperimental estimates of the impacts to "true impact" estimates provided by a random-assignment design used to assess the…