Longitudinal data from a large sample of twins participating in the Netherlands Twin Register (n = 42,827, age range 3-16) were analyzed to investigate the genetic and environmental contributions to childhood aggression. Genetic auto-regressive (simplex) models were used to assess whether the same genes are involved or whether new genes come into…

Background: We examined the longitudinal trajectory of substance use (binge drinking, marijuana use, and cocaine use) in relation to self-esteem from adolescence to young adulthood. Methods: Generalized estimating equation models were fit using SAS to investigate changes in the relation between self-esteem and each substance use (binge drinking,…

Emerging evidence suggests that family conflict shows continuity across generations and that intergenerational family conflict can be more intense and deleterious than conflict experienced in a single generation. However, few investigations have identified etiological mechanisms by which family conflict is perpetuated across generations.…

Purpose: We assess farm technology adoption in an integrated analysis of social networks and innovation in plantain production in Ghana. The paper explores the strength of social networks in the agricultural innovation systems (AISs) and the effect of AISs on adoption of improved farm technology. Methodology/Approach: The paper uses social network…

We examined the relations of short-term memory (STM), metalinguistic awareness (phonological, morphological, and orthographic awareness), and rapid automatized naming (RAN) to word reading in Korean, a language with a relatively transparent orthography. STM, metalinguistic awareness, and RAN have been shown to be important to word reading, but the…

Ethnic identity formation is a central developmental task that can become challenging when adolescents face a salient stressor, such as ethnic discrimination. Although ethnic identity and experiences with ethnic discrimination are thought to be associated, the temporal order of these constructs is unclear. In the current study, we examined (a) the…

The distinction between basic sciences and clinical knowledge which has led to a theoretical debate on how medical expertise is developed has implications for medical school and lifelong medical education. This longitudinal, population based observational study was conducted to test the fit of three theories--knowledge encapsulation, independent…

Within this "Adult Education Quarterly" ("AEQ") forum, the authors call for a dialogue and examination of research methods in the field of adult and continuing education. Using the article by Boeren as a starting point, the authors analyze both qualitative and quantitative research trends and advocate for more methodological…

The Test of Gross Motor Development--Second Edition (TGMD-2) is a widely used evaluation tool of children's fundamental motor skills (FMS). This study illustrates how exploratory structural equation modeling (ESEM) addresses current limitations associated with TGMD-2 factor structure. Using the normative dataset from the TGMD-2 manual, we test…

The literature on Automated Essay Scoring (AES) systems has provided useful validation frameworks for any assessment that includes AES scoring. Furthermore, evidence for the scoring fidelity of AES systems is accumulating. Yet questions remain when appraising the scoring performance of AES systems. These questions include: (a) which essays are…

Inferring causal effects of treatments is a central goal in many disciplines. The potential outcomes framework is a main statistical approach to causal inference, in which a causal effect is defined as a comparison of the potential outcomes of the same units under different treatment conditions. Because for each unit at most one of the potential…

In this research, the relational coordination model has been applied to prove learners' and instructors' high levels of satisfaction in e-learning. According to the model, organizations can obtain better results in terms of satisfaction by providing shared knowledge, shared goals and mutual respect mechanisms, supported by a frequent, timely and…

A diverse group of 20 high school students from four states in the US were individually provided with an engineering design challenge. Students chosen were in capstone engineering courses and had taken multiple engineering courses. As students considered the problem and developed a solution, observational data were recorded and artifacts…

The domain model is an essential part of an adaptive learning system. For each educational course, it involves educational content and semantics, which is also viewed as a form of conceptual metadata about educational content. Due to the size of a domain model, manual domain model creation is a challenging and demanding task for teachers or…

The fit of cognitive diagnostic models (CDMs) to response data needs to be evaluated, since CDMs might yield misleading results when they do not fit the data well. Limited-information statistic M[subscript 2] and the associated root mean square error of approximation (RMSEA[subscript 2]) in item factor analysis were extended to evaluate the fit of…