Researchers need to know what is an appropriate sample size for interview work, but how does one decide upon an acceptable number of people to interview? This question is not relevant to case study work where one would typically interview every member of a case, or in situations where it is both desirable and feasible to interview all target…

The Student Evaluation of Teaching (SET) instrument provides insight for instructors and administrators alike, often touting high response-rates to endorse their validity and reliability. However, response-rate alone omits consideration for "adequate quantity of 'observational sampling opportunity' (OSO) data points" (e.g., high student…

Coding is a process of assigning meaning to a given piece of evidence. Evidence may be found in a variety of data types, including documents, research interviews, posts from social media, conversations from learning platforms, or any source of data that may provide insights for the questions under qualitative study. In this study, we focus on text…

The Every Student Succeeds Act (ESSA) of 2015 (Public Law 114-95) requires each state to create a plan for its statewide accountability system. In particular, ESSA calls for state plans that include strategies for reporting education outcomes by grade for all students and for economically disadvantaged students, students from major racial and…

The present article describes the development and initial validation of the Inventory of Microaggressions Against Black Individuals (IMABI) using a sample of 385 undergraduates who self-identified as Black or African American. The IMABI is a 14-item, unidimensional measure of racial microaggressions that captures both microinsults and…

In regression analysis, the notion of population validity is of theoretical interest for describing the usefulness of the underlying regression model, whereas the presumably more important concept of population cross-validity represents the predictive effectiveness for the regression equation in future research. It appears that the inference…

Discusses the squared cross-validity coefficient as a measure of the predictive validity of a sample linear prediction equation. Presents sample-size tables that should result in very small discrepancies between the squared multiple correlation and the squared cross-validity correction, thus facilitating the selection of sample size for predictive…

Scale-up is the practice of introducing proven interventions into new settings with the goal of producing similarly positive effects in larger, more diverse populations. Scale-up "research" examines factors that influence the effectiveness of interventions as they are brought to scale across settings. This article has three objectives. First, it…

This article considers various kinds of probability and non-probability samples in both experimental and survey studies. Throughout, how a sample is chosen is stressed. Size alone is not the determining consideration in sample selection. Good samples do not occur by accident; they are the result of a careful design. (Author/JAZ)