ABSTRACT
This chapter outlines the process of turning abstract concepts such as health and job autonomy into measurable variables. The first section explains how variables are defined, created, and classified. The second section discusses basic terms having to do with measurement, such as validity and reliability. It also summarizes a study that illustrates how variables are used in research. Generally, constructs are developed from everyday ideas, with specific rules about how they’ll be turned into variables. Ultimately, variables are judged by how useful they are—do they support a prediction or serve as diagnostic tools? A variable is reliable to the extent that it gives the same answer on repeated measurements in the absence of change in the “true score” and in the absence of memory. Validity refers to the accuracy with which a variable measures the construct it is intended to measure. A valid variable must be reliable, but a reliable variable is not necessarily valid. To strengthen skills development, the last section of the chapter includes an excerpt from research about the relationship between a mother’s job characteristics and the type of child-care arrangements chosen. The excerpt illustrates the close interdependence among variables, theory, and analysis in social research.
