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…

Research articles published in 10 major journals during the years 1984-1987 were evaluated to determine how many satisfied the recommendations of the Council for Learning Disabilities' Research Committee on reporting subject data. Only 4 of the 277 articles included acceptable information in 7 recommended areas of subject data. (Author/JDD)

A meta-analysis was conducted on 44 educational studies that used either a (labelled) Hawthorne control group, a manipulation of Hawthorne effects, or a group designed to control for the Hawthorne effect. The sample included published journal articles, ERIC documents or unpublished papers, and dissertations. The studies were coded on 20 variables,…

A review of 208 studies of children with learning disabilities (LD) published in 10 major journals between 1988 and 1990 examined the extent to which recommendations concerning research design and reporting made in 1980 and 1984 have been implemented. The review found continuing problems, including imprecise subject descriptions, heterogeneous…

Conducting observational research in a cross-cultural context invokes a unique set of difficulties. This paper describes sources of bias and threats to validity that are specific to cross-cultural research. It describes problems of cross-cultural research designs for descriptive studies, comparative research, and experimental research and outlines…

It is difficult to conduct randomized field experiments. In the past decade, the use of alternative randomization plans and incentives has contributed to their operational feasibility; legal, ethical, and professional arguments for experimentation have matured; and expectations have become better aligned with practical constraints that are likely…

The evaluation design, which prescribes when and from whom to gather data, is described as significant because it can lend credibility to evaluation results. The objectives of this booklet are to aid the evaluator in: choosing a design; putting it into operation; and analyzing and reporting the data. Examples include both formative and summative…

The experience of a research group in studying Neighborhood Youth Corps (NYC) programs provides the framework for a discussion of the methodological difficulties of conducting research on disadvantaged groups. However, the report does not deal with the programs and operations of NYC itself. Four problem areas are described: (1) criterion, program,…

Evidence is presented that strengthens the argument against comparison group research strategies. Results from a study of youth attitudes related to the California Conservation Corps involving 528 participants and 668 comparisons indicate that the comparison group may not adequately represent the nontreatment state. (SLD)

This commentary on EC 605 442, which indicated long-term gains for children with autism who experienced intensive behavioral intervention as preschoolers, questions the magnitude of the student changes and their significance, because of concerns about the representativeness and comparability of the sample group and the failure to measure skills…

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…

This commentary on EC 605 442, which indicated long-term gains for children with autism who experienced intensive behavioral intervention as preschoolers, emphasizes the need for replication. The replication study should use random assignment to experimental and control groups, a larger sample of cases, standard diagnostic instruments to delineate…

While inquiry teaching has been a popular term in the social studies literature over the last decade, the empirical research appears to have paid little attention to specific inquiry models. All published papers and dissertations purporting to measure inquiry teaching for the five year period, January, 1967 through November, 1972 are reviewed and…

Recruiting schools and kids to participate in drug prevention evaluations is no longer, if it ever was, a "done deal." Since the mid-1980s, schools have been inundated with requirements for drug programs and requests to cooperate with program evaluations. As a consequence, both treatment and control schools are harder to find. In addition, many…

Research efforts have established that the Mantel-Haenszel procedure (MHP) is an effective method for detecting the presence of test items exhibiting differential item functioning (DIF). While the MHP has been advocated for situations where item response theory based methods may not be usable, recent findings have suggested that the performance of…