Many experimental designs in educational and behavioral research involve at least one level of clustering. Clustering affects the precision of estimators and its impact on statistics in cross-sectional studies is well known. Clustering also occurs in longitudinal designs where students that are initially grouped may be regrouped in the following…

When selecting a multilevel model to fit to a dataset, it is important to choose both a model that best matches characteristics of the data's structure, but also to include the appropriate fixed and random effects parameters. For example, when researchers analyze clustered data (e.g., students nested within schools), the multilevel model can be…

What causes the literacy gap and can schools compensate for it? The authors investigated 3 drivers of the gap: preliteracy knowledge, schooling, and the summer vacation. Longitudinal literacy data over 5 time points were collected on 126 five-year-olds attending higher or lower socioeconomic status (SES) schools during their first 15 months of…

The purposes of this study were 1) Compare analytical thinking ability by testing the same sets of students 5 times 2) Develop and verify whether analytical thinking ability of students corresponds to second-order growth curve factors model. Samples were 1,093 eighth-grade students. The results revealed that 1) Analytical thinking ability scores…

The authors used a person-centered, longitudinal approach to identify and evaluate naturally occurring combinations of intrinsic and extrinsic motivations among 490 third- through fifth-grade students. Cluster analysis revealed 3 groups, characterized by high levels of both motivations ("high quantity"): high intrinsic motivation but low…

Based on a longitudinal sample of 1,452 African American and European American adolescents and their parents, parenting practices (i.e., monitoring, warmth, and autonomy support) at 7th grade had significant indirect effects on college enrollment 3 years post high school, through their effects on aspirations, school engagement, and grade point…

Evidence is building regarding the association between inadequate amounts of sleep and the risk of obesity, especially in younger children. Less is known about the relationship between change in sleep and change in weight during adolescence. The objective of this study was to examine the longitudinal relationship between change in sleep duration…

In 2000, the Texas Higher Education Coordinating Board (THECB) adopted Closing the Gaps by 2015: The Texas Higher Education Plan. This new master plan set goals for Texas higher education in participation, success, research, and excellence. The plan acknowledged a shortfall related to projected demographic shifts in both the number of degrees and…

Although skill shortages are often portrayed as a significant problem for the Australian economy, there is surprisingly little evidence about their prevalence, causes and consequences. It is difficult to find robust evidence about where skill shortages occur, why they occur, what businesses try to do about them and whether their responses are…

Students must be sufficiently motivated in order to achieve the intended learning outcomes of their college courses. Research in education and psychology has found motivation to be context-dependent. Therefore, students' motivation is likely to differ from one semester to the next according to which courses students are taking. However, there are…

The impact of Comprehensive School Physical Activity Programs (CSPAPs) on urban children's, educators', and parents' physical activity (PA) is relatively unknown. The purpose of this study was to explore overall changes in student, educator, and parent PA after an 8-month CSPAP-based program. This longitudinal, exploratory study implemented a…

The purposes of this study are: (1) to demonstrate the superiority of simple ridge regression over ordinary least squares regression through theoretical argument and empirical example; (2) to modify ridge regression through use of the variance normalization criterion; and (3) to demonstrate the superiority of simple ridge regression based on the…

The application of a multivariate analytic technique for the analysis of data from longitudinal designs with multiple dependent variables is presented. The technigue is the multivariate generalization of univariate repeated measures ANOVA. An application of the technique to data collected using materials from the Asian Studies Curriculum Project…