Principal leadership has been widely regarded as a powerful catalyst for school improvement and student learning. This article presents a multivariate meta-analysis of 42 empirical studies, published between 2000 and 2020, that examined the effects of principal leadership on student achievement in the United States. The focus is on the conceptual…

Multilevel meta-analysis is an innovative synthesis technique used for the quantitative integration of effect size estimates across participants and across studies. The quantitative summary allows for objective, evidence-based, and informed decisions in research, practice, and policy. Based on previous methodological work, the technique results in…

Randomized experiments are generally considered to provide the strongest basis for causal inferences about cause and effect. Consequently randomized field trials have been increasingly used to evaluate the effects of education interventions, products, and services. Populations of interest in education are often hierarchically structured (such as…

Single case designs (SCDs) are short time series that assess intervention effects by measuring units repeatedly over time both in the presence and absence of treatment. For a variety of reasons, interest in the statistical analysis and meta-analysis of these designs has been growing in recent years. This paper proposes modeling SCD data with…

The concept of bidirectionality represents a process of mutual influence between parent and child, whereby each influences the other as well as the dyadic relationship. Despite the widespread acceptance of bidirectional models of influence, there is still a lack of integration of such models in current research designs. Research on…

Use of multivariate analysis (e.g., multivariate analysis of variance) is common when normally distributed outcomes are collected in intervention research. However, when mixed responses--a set of normal and binary outcomes--are collected, standard multivariate analyses are no longer suitable. While mixed responses are often obtained in…

The rapid pace of change for knowledge workers competing globally necessitates ongoing continuous learning. Increasingly, knowledge workers will need to be ready--willing and able--to engage in self-directed learning. This makes it important to understand what factors in the work environment might be related to the self-directed learning…

The purpose of this research to investigate the heterogeneity of per-pupil expenditure (PPE) slope estimates in predicting student achievement. The research question guiding this project is: how does the measured relationship between per-pupil expenditure vary across studies that use different models? In concert with SREE's 2012 conference mission…

This study examined the impact of different levels of task difficulty and expertise on self-efficacy judgments. In addition, the study examines how self-efficacy judgments affect the amount of mental effort investment and task performance under different levels of task difficulty and expertise. Results from this study are used to build a…

A longstanding and fundamental debate in developmental science is whether knowledge is acquired through domain-specific or domain-general mechanisms. To date, there exists no tool to determine whether experimental data support one theoretical approach or the other. In this article, we argue that the U- and N-shaped curves found in a number of…

This study aims to investigate two expert ecology teachers' ability to attend to essential details in a complex environment during a field excursion, as well as how they teach this ability to their students. In applying a cognitive dual-memory system model for learning, we also suggest a rationale for their behaviour. The model implies two…

In practice, the inclusion of correlated residuals in latent-variable models is often regarded as a statistical sleight of hand, if not an outright form of cheating. Consequently, researchers have tended to allow only as many correlated residuals in their models as are needed to obtain a good fit to the data. The current article demonstrates that…

Coefficient Kappa is generally defined in terms of procedures of computation rather than in terms of a population. Here a population definition is proposed. Factors influencing the magnitude of Kappa are identified. Strategies to improve reliability are proposed, including that of combining multiple unreliable diagnoses. (Author/CTM)

In experimentation where change in X produces a change in Y, the researcher must identify, measure, and control intervening variables by experimental design or statistical procedure. (Author)

The usual interpretation of suppressor effects in a multiple regression equation assumes that the correlations among variables have been generated by a particular structural model. How such a regression equation is interpreted is shown to be dependent on the structural model deemed appropriate. (Author/JKS)