Propensity score (PS) adjustments have become popular methods used to improve estimates of treatment effects in quasi-experiments. Although researchers continue to develop PS methods, other procedures can also be effective in reducing selection bias. One of these uses clustering to create balanced groups. However, the success of this new method…

The present study illustrates the utility of applying multilevel mixture models in educational research, using data on the homework behavior of 1,812 Swiss eighth-grade students in French as a second language. A previous person-centered study identified 5 homework learning types characterized by different patterns of high or low homework time and…

Latent class analysis is an analytic technique often used in educational and psychological research to identify meaningful groups of individuals within a larger heterogeneous population based on a set of variables. This technique is flexible, encompassing not only a static set of variables but also longitudinal data in the form of growth mixture…

Argument writing is challenging for elementary students. Previous experimental research has focused on scaffolding rhetorical goals, leaving content goals relatively unexplored. In a randomized experiment, 73 students in grades 5, 6, and 7 wrote persuasive texts about difficult-to-classify vertebrates. Each student received one of three sets of…

Statistics learners often bypass the critical step of understanding a problem before executing solutions. Worked-out examples that identify problem information (e.g., data type, number of groups, purpose of analysis) key to determining a solution (e.g., "t" test, chi-square, correlation) can address this concern. The authors examined the…

Classification studies are important for practitioners who need to identify individuals for specialized treatment or intervention. When interventions are irreversible or misclassifications are costly, information about the proficiency of different classification procedures becomes invaluable. This study furnishes information about the relative…