Multilevel models are widely used in education and social science research. However, the effects of omitting levels of the hierarchy on the variance decomposition and the clustering effects have not been well documented. This paper discusses how omitting one level in three-level models affects...

In experimental designs with nested structures entire groups (such as schools) are often assigned to treatment conditions. Key aspects of the design in these cluster randomized experiments include knowledge of the intraclass correlation structure and the sample sizes necessary to achieve...

Evidence from Project STAR has suggested that on average small classes increase student achievement. However, thus far researchers have focused on computing mean differences in student achievement between smaller and larger classes. In this study I focus on the distribution of the small class...

This study examines gender differences in the earnings of young adults in the 1980s and 1990s. We determine changes in the gender gap over time in the middle, the tails, and the variability of the earnings distribution. We employ data from two longitudinal, nationally probability samples of high...

This study examines high school effects on the labor market success of young adults, above and beyond individual and family characteristics. We employ data from two longitudinal, nationally probability samples: the National Longitudinal Study and the High School and Beyond study and the 5th and...

This study examines the wage gender gap of young adults in the 1970s, 1980s, and 2000 in the US. Using quantile regression we estimate the gender gap across the entire wage distribution. We also study the importance of high school characteristics in predicting future labor market performance. We...

This study examines the gender gap in wages of young adults in the late 1970s, mid 1980s, and 2000, in the middle and the tails of the wage distribution using quantile regression. We also examine the importance of school quality indicators in predicting future labor market performance. We...

Meta-analytic methods have been widely applied to education, medicine, and the social sciences. Much of meta-analytic data are hierarchically structured since effect size estimates are nested within studies, and in turn studies can be nested within level-3 units such as laboratories or...

We examined the persistence of teacher effects from grade to grade on lower-performing students using high-quality experimental data from Project STAR, where students and teachers were assigned randomly to classrooms of different sizes. The data included information about mathematics and reading...

Multilevel models are widely used in education and social science research. However, theeffects of omitting levels of the hierarchy on the variance decomposition and the clusteringeffects have not been well documented...