Multivariate analysis of variance (MANOVA) is a statistical method used to examine group differences on multiple outcomes. This article reports results of a review of MANOVA in gifted education journals between 2011 and 2017 (N = 56). Findings suggest a number of conceptual and procedural misunderstandings about the nature of MANOVA and its…

This brief paper introduces a new approach to assessing the trustworthiness of research comparisons when expressed numerically. The 'number needed to disturb' a research finding would be the number of counterfactual values that can be added to the smallest arm of any comparison before the difference or 'effect' size disappears, minus the number of…

In a cluster-randomized study, we investigate the impact of an argument-based approach to teaching science in elementary school on science learning and critical thinking skills. Forty-eight schools participated in the study, with data on 9,963 students across the 2 years of the intervention. Annual standardized tests assessing science content…

The purpose of this study was to examine evidence of a hypothesized shift in the operative research paradigms in music education during the first quarter century of the publication of the "Journal of Research in Music Education," during the period 1953 to 1978. This shift was from humanities-oriented historical and philosophical studies…

In the era of contemporary society, which revolves around the fast information science revolution, the pupil is no longer just an observer in the educational process but rather an active constructor of one's own knowledge. Current didactic theories proclaim teaching, in which the teacher is an instructor and a facilitator, and as such should…

This is an experimental study, made used of the non-randomized experimental and control groups, pretest-posttest designs. The experimental and control groups were two separate intact classes in Algebra. For a period of twelve sessions, the experimental group was subjected to the scientific heuristic method, but the control group instead was given…

Existing studies report on the importance of instilling environmental literacy among students from an early stage of schooling to enable them to adopt more pro-environmental behaviors in the near future. This quasi-experimental study was designed to compare the level of environmental literacy among two groups of students: the experimental group (N…

A pretest-posttest comparison group design was used to investigate the effects of a semantic mapping lesson plus visual display versus a semantic mapping lesson alone on adolescents' with learning disabilities (LD) ability to gain and maintain factual knowledge from expository social studies material. In addition, a posttest only comparison group…

The present article provides a primer on using effect sizes in research. A small heuristic data set is used in order to make the discussion concrete. Additionally, various admonitions for best practice in reporting and interpreting effect sizes are presented. Among these is the admonition to not use Cohen's benchmarks for "small," "medium," and…

Aptitude-treatment interaction (ATI) studies have been used with some frequency, yet many researchers do not understand fully what interaction effects are. Because the means for interactions involve fewer persons per mean, power to detect interaction effects is typically smallest for the highest-order interaction in a given design. This phenomenon…

The following article provides a brief primer and overview of multilevel and hierarchical linear modeling. The school-effects model with random effects is illustrated with a heuristic dataset. Finally, recommendations are presented for researchers studying learning disabilities who would like to utilize this methodology.

Three procedures for evaluating the replicability of descriptive discriminant analysis (DDA) results are discussed. The techniques include cross-validation, the jackknife, and the bootstrap. Discriminant analysis is a multivariate technique used when group membership or classification is the focus of the analysis. DDA is used to describe major…

A new method for evaluating model fit that is easy to use and interpret is presented. The new method, which uses a binomial test of the number of hypotheses (paths) in a model that are supported by the data, has heuristic value when considering problems associated with other goodness-of-fit measures. An application of the binomial test as a…

The present paper suggests that multivariate techniques are very important in social science research, and that canonical correlation analysis may be particularly useful. The logic of canonical analysis is explained and discussed. The necessity of using replicability/generalizability analyses is argued. It is suggested that cross-validation…

The use of Procrustean rotation as a procedure for assessing the invariance of study results is proposed. Researchers have long relied on significance testing as a measure of judging the worthiness of empirical findings. However, significance testing has come under fire because it does not provide information about the importance or replicability…