Qualitative Comparative Analysis, Necessary Conditions, and Limited Diversity

Abstract

We discuss a recent development in the set theoretic analysis of data sets characterized by limited diversity. Ragin, in developing his Qualitative Comparative Analysis (QCA), developed a standard analysis that produces parsimonious, intermediate, and complex Boolean solutions of truth tables. Schneider and Wagemann argue this standard analysis procedure is problematic and develop an enhanced standard analysis (ESA). We show, by developing Schneider and Wagemann’s discussion of Stokke’s work on fisheries conservation and by discussing a second illustrative truth table, that ESA has problematic features. We consider how scholars might proceed in the face of these problems, considering the relations between limited diversity and the different methods of reducing truth tables instantiated in Ragin’s QCA and Baumgartner’s Coincidence Analysis.