Randomized experiments involving education interventions are typically implemented as cluster randomized trials, with schools serving as clusters. To design such a study, it is critical to understand the degree to which learning outcomes vary between versus within clusters (schools), specifically the intraclass correlation coefficient. It is also…

Covariate adjustment can increase the precision of estimates by removing unexplained variance from the error in randomized experiments, although chance covariate imbalance tends to counteract the improvement in precision. The author develops an easy measure to examine chance covariate imbalance in randomization by standardizing the average…

Background: Results from MDRC's longitudinal, random-assignment evaluation of career-academy high schools reveal that several years after high-school completion, those randomized to receive the academy opportunity realized a $175 (11%) increase in monthly earnings, on average. Objectives: In this paper, I investigate the impact of duration of…

Background: Many university departments use students' evaluations of teaching (SET) to compare and rank courses. However, absenteeism from class is often nonrandom and, therefore, SET for different courses might not be comparable. Objective: The present study aims to answer two questions. Are SET positively biased due to absenteeism? Do…

Objectives: Group-randomized designs are well suited for studies of professional development because they can accommodate programs that are delivered to intact groups (e.g., schools), the collaborative nature of professional development, and extant teacher/school assignments. Though group designs may be theoretically favorable, prior evidence has…

Both true experiments and regression discontinuity (RD) designs produce unbiased estimates of effects. However, true experiments are, of course, often criticized on equity grounds, whereas RD designs entail sacrifices in terms of statistical precision. In this article, a hybrid of true experiments and RD designs is considered. This hybrid entails…

Evaluation designs for social programs are developed assuming minimal or no disruption from external shocks, such as natural disasters. This is because extremely rare shocks may not make it worthwhile to account for them in the design. Among extreme shocks is the 2010 Chile earthquake. Un Buen Comienzo (UBC), an ongoing early childhood program in…

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 involve knowledge of the intraclass correlation structure, the effect size, and the sample sizes necessary to achieve adequate power to detect the treatment…

Recent meta-analyses of drug-court studies recognized the poor methodological quality of the evaluations, with only a few being randomized. This article critiques the design of the randomized studies from a statistical perspective. Learning points are identified for future drug-court studies and are applicable to evaluations both of other…

The determinants of sentencing are of much interest in criminal justice and legal research. Understanding the determinants of sentencing decisions is important for ensuring transparent, consistent, and justifiable sentencing practice that adheres to the goals of sentencing, such as the punishment, rehabilitation, deterrence, and incapacitation of…

Background: Surveys of community-based programs are difficult to conduct when there is virtually no information about the number or locations of the programs of interest. This article describes the methodology used by the Helping Young Smokers Quit (HYSQ) initiative to identify and profile community-based youth smoking cessation programs in the…

This article reports results from a student survey fielded using an experimental design with 14 Kentucky school districts. Seven of the 14 districts were randomly assigned to implement the survey with active consent procedures; the other seven districts implemented the survey with passive consent procedures. We used our experimental design to…

In social policy evaluations, the multiple testing problem occurs due to the many hypothesis tests that are typically conducted across multiple outcomes and subgroups, which can lead to spurious impact findings. This article discusses a framework for addressing this problem that balances Types I and II errors. The framework involves specifying…

Evaluations that combine social science and law have tremendous potential to illuminate the effects of governmental policies and yield insights into how effectively policy makers' efforts achieve their aims. This potential is infrequently achieved, however, because such interdisciplinary research contains often overlooked substantive and…

The state of California passed the Smoke-Free Workplace Act on January 1, 1995. This legislation effectively banned indoor smoking in all public and private workplaces including restaurants. Many restaurant owners, especially owners of restaurants that served alcohol, opposed the ban for fear that their businesses would be affected adversely…