(Measures) Fundamentals of Measurement
You will recall from Chapter 2 that the research hypothesis involves a prediction about the relationship between or among two or more variables—for instance, the relationship between self-esteem and college performance or between study time and memory. When stated in an abstract manner, the ideas that form the basis of a research hypothesis are known as conceptual variables. Behavioral scientists have been interested in such conceptual variables as self-esteem, parenting style, depression, and cognitive development.
Measurement involves turning conceptual variables into measured variables, which consist of numbers that represent the conceptual variables. 1 The measured variables are frequently referred to as measures of the conceptual variables. In some cases, the transformation from conceptual to measured variable is direct. For instance, the conceptual variable “study time” is straightforwardly represented as the measured variable “seconds of study.” But other conceptual variables can be assessed by many different measures. For instance, the conceptual variable “liking” could be assessed by a person rating, from one to ten, how much he or she likes another person. Alternatively, liking could be measured in terms of how often a person looks at or touches another person or the number of love letters that he or she writes. And liking could also be measured using physiological indicators such as an increase in heart rate when two people are in the vicinity of each other.
