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Analyzing Relationships of Necessity Not Just in Kind But Also in Degree: Complementing fsQCA With NCA
1Department of Political Science and Public Administration, Vrije Universiteit Amsterdam, Amsterdam, the Netherlands.
Abstract:
Analyzing relationships of necessity is important for both scholarly and applied research questions in the social sciences. An often-used technique for identifying such relationships-fuzzy set Qualitative Comparative Analysis (fsQCA)-has limited ability to make the most out of the data used. The set-theoretical technique fsQCA makes statements in kind (e.g., "a condition or configuration is necessary or not for an outcome"), thereby ignoring the variation in degree. We propose to apply a recently developed technique for identifying relationships of necessity that can make both statements in kind and in degree, thus making full use of variation in the data: Necessary Condition Analysis (NCA). With its ability to also make statements in degree ("a specific level of a condition is necessary or not for a specific level of the outcome"), NCA can complement the in kind analysis of necessity with fsQCA.
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