Introduction

This introduction presents an overview of the key concepts discussed in the subsequent chapters of this book. The book contains summary chapters about four facets of the communication discipline that use quantitative measures. The chapters identify how the editors made their decisions to profile measures. It includes summaries (what we call profiles) of measures commonly used in communication research. The profiles are organized alphabetically by measure name rather than in categories, not only to facilitate finding specific measures, but because some measures would fall into more than one category. The authors use standard definitions of validity and reliability in their profiles. Kerlinger (1986) and Babbie (1992) provided the definitions and distinctions used here: Reliability is the dependability, predictability, stability, or precision of a measure. Validity occurs when a measure is actually measuring what it is supposed to measure. Readers will notice that important measures developed outside the communication field are not included in this volume.