Judging the success of school reform requires an interpretative context in which to judge whether effects obtained are large enough to be important or so small as to be a disappointment. The logic of school reform suggests two frameworks with which to judge the importance of effects. One is the...

The last three decades the accumulation of quantitative research evidence has led to the development of systematic methods for combining information across samples of related studies. Although a few methods have been described for accumulating research evidence over time, meta-analysis is widely...

Field experiments that involve nested structures may assign treatment conditions either to entire groups (such as classrooms or schools), or individuals within groups (such as students). Since field experiments involve clustering, key aspects of their design include knowledge of the intraclass...

Previous findings from experimental and non-experimental studies have demonstrated that teachers differ in their effectiveness. In addition, evidence from non-experimental studies has indicated that teacher effects can last up to five years. This study used high-quality data from a four-year...

Given that previous findings on the social distribution of the effects of small classes have been mixed and inconclusive, in the present study I attempted to shed light on the mechanism through which small classes affect the achievement of low- and high-achieving students. I used data from a...

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...