Research in fields other than education has found that studies with small sample sizes tend to have larger effect sizes than those with large samples. This article examines the relationship between sample size and effect size in education. It analyzes data from 185 studies of elementary and secondary mathematics programs that met the standards of…

Explains the characteristics and importance of random assignment in experimental research on education. Considers factors supporting causal inferences, the nature of "assignment units," differences between random sampling and random assignment, the characteristics of randomization tests, forms of random assignment, and effects of experimental…

THE MANY ACTIVITIES RESULTING FROM THE RECENT EMPHASIS UPON IMPROVING EDUCATION SHOULD CONCERN THE MAJOR PROBLEMS, RESEARCH TOPICS, AND PRIORITIES IDENTIFIED THROUGH A SUGGESTED SYSTEM OF VOCATIONAL EDUCATION BOOKKEEPING IN WHICH RESULTS ARE REVIEWED BY APPROPRIATE STAFF AND RESOURCE PERSONNEL FROM BUSINESS, INDUSTRY, COLLEGES, AND UNIVERSITIES.…

Advantages and disadvantages of nonexperimental paradigms in mathematics education are discussed. Suggestions are made for action toward establishing such designs as quality research. (MP)

The problem of spurious significance in multivariate exploratory research is discussed. When a very large number of statistical tests are performed, many tests will be significant on the basis of chance alone. To counter this problem, the use of two sign tests to analyze sets of results has been suggested; the chance expectation [CE test] assesses…

Exploratory research with large numbers of variables and even larger numbers of relationships is likely to result in frequent Type II errors; that is falsely accepting an incorrect null hypotheses. There are three ways of reducing Type II errors: (1) choosing a lower significance level, which then increases the probability of Type I error; (2)…

Studies carried out in connection with the activities of the American Educational Research Association (AERA) Committee on Access to do Research in the Public Schools.

Documenting treatment integrity is an important issue in research and practice in any discipline concerned with prevention and intervention. However, consensus concerning the dimensions of treatment integrity and how they should be measured has yet to emerge. Advances from three areas in which significant treatment integrity work has taken…

The purpose of this paper is to summarize and evaluate experiments which examined the effects of teacher questions on student achievement. The studies reviewed are of two types: (a) training experiments, in which the independent variable is teacher training; and (b) skills experiments, in which the frequency and manner of use of a teaching skill…

Problems with conducting randomized field experiments in education are explored. Focus is on problems encountered while evaluating a group of dropout prevention projects. Project planners were asked to manipulate the subject eligibility criteria until they identified as eligible three to four times as many students as they could serve. They were…

The paper discusses a number of issues concerning the practical usefulness of cognitive psychology research, and presents a case study of pilot training methods to illustrate a model of research processes that produces outcomes which contribute to both basic and applied research goals. Research studies are described as varying in the degree to…