Decomposing variables into between and within components are often required in multilevel analysis. This method of decomposition should not ignore possible unreliability of an observed group mean (i.e., arithmetic mean) that is due to small cluster sizes and can lead to substantially biased estimates. Adjustment procedures that allow unbiased…

This article is premised on the observation that in educational research there is an increasing use of terminology and concepts related to the field of complexity and the study of complex physical, biological, and social systems. As we are at an early stage in this cross-fertilization of complex systems ideas and methods in educational research,…

The complex dynamical systems (CDS) approach consists of a family of theories emanating largely from the exact sciences. These theories share a common focus on the behavior of systems and their interrelated parts and are concerned with the processes of stability, change, and unpredictability in those systems. This article takes stock of the…

In this commentary, we propose a framework for applying the Complex Dynamical Systems (CDS) approach in educational research. Drawing on the conceptual articles in the special issue for ontological, theoretical, and methodological principles, and on the empirical articles for examples of these principles' application, we suggest six interdependent…

Lord's Paradox occurs when a continuous covariate is statistically controlled for and the relationship between a continuous outcome and group status indicator changes in both magnitude and direction. This phenomenon poses a challenge to the notion of evidence-based policy, where data are supposed to be self-evident. We examined 50 effect size…

Randomized controlled trials are not always feasible in educational research, so researchers must use alternative methods to study treatment effects. Propensity score matching is one such method for observational studies that has shown considerable growth in popularity since it was first introduced in the early 1980s. This paper outlines the…

Educational stakeholders are keen to know the magnitude and importance of different interventions. However, the way evidence is communicated to support understanding of the effectiveness of an intervention is controversial. Typically studies in education have used the standardised mean difference as a measure of the impact of interventions. This…

The Institute of Education Sciences has funded more than 100 experiments to evaluate educational interventions in an effort to generate scientific evidence of program effectiveness on which to base education policy and practice. In general, these studies are designed with the goal of having adequate statistical power to detect the average…

There is general agreement that meta-analysis is an important tool for synthesizing study results in quantitative educational research. Yet, a shared feature of many meta-analyses is a failure to report sufficient information for readers to fully judge the reported findings, such as the populations to which generalizations are to be made,…

Gives an overview of three of the myths that F. N. Kerlinger (1959, 1960) identified as pervading educational research. Explores the myths of methods, practicality, and statistics, and analyzes the degree to which they have been overcome or still exist. (SLD)

The purpose of the present study was to examine knowledge retention as a variable of students graded by the contract and traditional grading methods in order to provide for teachers further evidence for choosing a grading method. (Author)

Two studies designed to analyze the role of reflection in logical deductive reasoning were conducted. (Editor)

Student performance in an individually-paced PSI course in introductory psychology is described. (Editor)

The myth that research should have practicality as its principal aim was attacked by F. N. Kerlinger in many of his publications. However, a review of current educational research textbooks suggests that the field of education is still focused more on applied than on basic research. (SLD)

This field study was designed as an examination of the effects of stating self-expectancy for complex learning tasks administered under typical classroom conditions. (Author/RK)