In this innovative approach to the practice of social science, Charles Ragin explores the use of fuzzy sets to bridge the divide between quantitative and qualitative methods. Paradoxically, the fuzzy set is a powerful tool because it replaces an unwieldy, "fuzzy" instrument--the variable, which establishes only the positions of cases relative to each other, with a precise one--degree of membership in a well-defined set.

Ragin argues that fuzzy sets allow a far richer dialogue between ideas and evidence in social research than previously possible. They let quantitative researchers abandon "homogenizing assumptions" about cases and causes, they extend diversity-oriented research strategies, and they provide a powerful connection between theory and data analysis. Most important, fuzzy sets can be carefully tailored to fit evolving theoretical concepts, sharpening quantitative tools with in-depth knowledge gained through qualitative, case-oriented inquiry. This book will revolutionize research methods not only in sociology, political science, and anthropology but in any field of inquiry dealing with complex patterns of causation.

Contents:

Chapter l: Introduction

Chapter 2: Diversity-Oriented Research: Between Complexity and Generality

Chapter 3: Constituting Populations

Chapter 4: Studying Cases as Configurations

Chapter 5: Causal Complexity

Chapter 6: The Logic of Diversity-Oriented Research

Chapter 7: Fuzzy Sets and the Study of Diversity

Chapter 8: Using Fuzzy Sets to Constitute Cases and Populations

Chapter 9: Fuzzy Sets and Necessary Conditions

Chapter 10: Using Fuzzy Sets to Study Sufficient Conditions

Chapter 11: Causal Complexity: Applying Fuzzy-Set Methods

Chapter 12: Fuzzy Sets and the Dialogue Between Ideas and Evidence