Students often believe that statistical significance is the only determinant of whether a quantitative result is "important." In this paper, I review traditional null hypothesis statistical testing to identify what questions inferential statistics can and cannot answer, including statistical significance, effect size and direction,…

The aim of this paper is to introduce a software that is appropriate for the generalizability theory for not only balanced but also unbalanced data sets. Because it is possible to have unbalanced data sets while conducting a study, the researchers have devised an easy solution, other than deleting data, to balance the design to cope with this…

Randomized trials play an important role in estimating the effect of a policy or social work program in a given population. While most trial designs benefit from strong internal validity, they often lack external validity, or generalizability, to the target population of interest. In other words, one can obtain an unbiased estimate of the study…

Design-based research (DBR) is a new methodological framework that was developed in the context of the learning sciences; however, it has not been used very often in the field of gifted education. Compared with other methodologies, DBR is more process-oriented and context-sensitive. In this methodological brief, the authors introduce DBR and…

Regression discontinuity (RD) analysis is a rigorous nonexperimental approach that can be used to estimate program impacts in situations in which candidates are selected for treatment based on whether their value for a numeric rating exceeds a designated threshold or cut-point. Over the last two decades, the regression discontinuity approach has…

There are situations within middle school settings where measurements of students and teachers are used for high-stakes decisions. For example, student performance is used as an indicator of teacher quality or determines student eligibility for particular types of support services. Given the high-stakes nature of these types of assessments,…

A structural equation modeling approach to scale reliability evaluation can be employed to estimate generalizability theory indexes in settings where sampling of subjects and conditions is carried out. In one- and two-facet crossed designs, it is demonstrated how this method can be used to obtain estimates of relative generalizability…

This paper presents a large-scale, comprehensive test of generalized trust across 31 nations. I pay particular attention to the theory and measurement of voluntary associations in promoting trust, hypothesizing that voluntary associations connected to other voluntary associations are more beneficial for the creation of generalized trust than…

The zeitgeist for reform in education precipitated a number of changes in assessment. Among these are performance assessments, sometimes linked to "high stakes" accountability decisions. In some instances, the trustworthiness of these decisions is based on variance components and error variances derived through generalizability theory.…