QCA for Mathematicians

For mathematicians, programmers and others who are interested in the technical details of how QCA operates, here are a few pieces that I recommend:

Charles Ragin (1987) The Comparative Method. The foundational text that introduced QCA also covers how Boolean Algebra, DeMorgan's Laws and Quine-McLuskey minimization are used to implement the technique. But note that the text uses non-standard notation and the discussion is simplified for social scientists.

Jerry Mendel (Professor Emeritus, USC) has the best work in QCA for people with stronger mathematical backgrounds. He's a retired professor of electrical engineering, and author of the type-2 fuzzy set textbook, Explainable Uncertain Rule-Based Fuzzy Systems (3e, 2024). He's published about a dozen articles examining, explicating, and in some cases correcting or improving, the mathematical foundation of QCA. He also participated in an extended discussion with Ragin about QCA, which he helpfully published online. Start with these:

• Mendel, Jerry M. (2013) "The Essence of Fuzzy Set Qualitative Comparative Analysis (fsQCA)." Soft Computing: State of the Art Theory: 25–37.

• Mendel, Jerry M. and Mohammad M. Korjani. (2013) "Theoretical Aspects of Fuzzy Set Qualitative Comparative Analysis (fsQCA)." Information Sciences 237:137–161.

• J.M. Mendel (with contributions from Prof. Ragin), fsQCA: Dialog Between Jerry M. Mendel and Charles C. Ragin, 2e USC-SIPI Report #411, January 2012.