What's this r? A Correlational Approach to Explaining Validity, Reliability and Objectivity Coefficients

Abstract

Introducing students to measurement concepts poses unique instructional challenges; yet, the importance of measurement issues for all data collection scenarios (e.g., the classroom, individual clients, sporting events) requires that students understand the value of basic measurement procedures. Illustrating the basic measurement topics of reliability and validity via the Pearson's r correlation coefficient is one method for bridging the instructional gap. This teaching tool provides a brief discussion of reliability and validity for norm-referenced testing using the correlation coefficient as a common statistical procedure. Instructional exercises follow that illustrate the application of the Pearson's r to issues of reliability and validity. Teachers could use this presentation to better acquaint students with the relations between correlation coefficients and measurement procedures.