Sophisticated simulations using computer graphics can lead to students deducing virtually all conditions of the Central Limit Theorem. Eight graphs illustrate the discussion. (MNS)

The most familiar models of item response theory are defined at the level of individual subjects. It is possible, however, to define such models for groups of subjects. This paper discusses group-level item response models, their uses, and their relationships to subject-level models. (Author/JKS)

Six behavioral statistics textbooks listed by their publishers as "bestsellers" during 1982 were reviewed by the author. The intent was to detect the presence of and to discuss the nature of some theoretical inferential inaccuracies, misinterpretations and errors. (Author/LMO)

In everyday reasoning, people use statistical heuristics (judgmental tools that are rough intuitive equivalents of statistical principles). Use of statistical heuristics is more likely when (1) sampling is clear, (2) the role of chance is clear, (3) statistical reasoning is normative for the event, or (4) the subject has had training in…

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…

Describes the Expectations About Counseling (EAC) questionnaire, a promising instrument that may help standardize research on expectations. Used the EAC to compare expectations of student nonclients, student clients, and nonstudent clients (N=78). No statistically significant differences were found among the groups. (BH)

The author argues that he properly used the National Longitudinal Survey sample in his analysis which concluded that private schooling is not superior to public schooling with regard to student's academic achievement, a conclusion contrary to that reached by Coleman and Hoffer in their analysis of the same sample. (RM)

This paper is concerned with problems in assessing the behavior of trace substances introduced into natural systems, sampling models of five classes that might be used in the study of contaminants are reviewed. Adaptation of an industrial experimentation method and techniques used in economic geology to ecological sampling is recommended.…

The National Assessment of Educational Progress (NAEP) Validity Studies Panel undertook a systematic analysis to consider the domain of validity threats to NAEP and to identify the most urgent research priorities. A framework of six broad categories was developed: (1) the constructs measured within each of NAEP's subject domains; (2) the manner in…

Stepwise methods are frequently employed in educational and psychological research, both to select useful subsets of variables and to evaluate the order of importance of variables. Three problems with stepwise applications are explored in some detail. First, computer packages use incorrect degrees of freedom in their stepwise computations,…

This paper discusses the impact of sampling error on the construction of confidence intervals around effect sizes. Sampling error affects the location and precision of confidence intervals. Meta-analytic resampling demonstrates that confidence intervals can haphazardly bounce around the true population parameter. Special software with graphical…

This paper suggests that statistical significance testing and effect size are two sides of the same coin; they complement each other, but do not substitute for one another. Good research practice requires that both should be taken into consideration to make sound quantitative decisions. A Monte Carlo simulation experiment was conducted, and a…

Against an historical backdrop, this paper summarizes four uses of intraclass correlation of importance to contemporary researchers in the behavioral sciences. First, it shows how the intraclass correlation coefficient can be used to adjust confidence intervals for statistical significance testing when data are intracorrelated and the independence…

Certain noneconomic factors in collective bargaining are directly related to the negotiator's personal inclination to settle for the new contract. In this study, the pattern of relationships between the parties, the nature of the work itself, favorable recognition, team policy, and interpersonal relationships proved to be significantly related to…

This study attempts to assess the effects of ethnicity on educational achievement. (Author)