Qualitative and Quantitative Methods: Can They Be Joined? (Not By Causal Process Observations!)

Brady, Collier and Seawright have argued that “causal process observations” can be adjoined to “data set observations.” This implies that qualitative methods can be used to add information to problematic quantitative data sets and hence can solve quantitative research design issues. In a recent symposium in Political Analysis I argued that such qualitative information cannot be adjoined in any meaningful way to quantitative data sets. In that symposium the original authors offered several defenses. Here I consider those defenses. In particular, I argue that the “causal process observations” are useful either for the explanation of specific events, or to help in the theory building process (or in any other way that qualitative analysts find them useful); but, they are not capable of being “adjoined” to standard quantitative data. Furthermore, there appears to be ambiguity in how BCS use the term ”causal process observation,” and whether the BCS usage covers items that look more like “data set observations.” ∗Department of Politics; New York University; New York, NY 10003 USA; [email protected]. Thanks to Henry Brady and David Collier for many extremely civil conversations, and to Gary King, Bernard Manin, Adam Przeworski and Jas Sekhon for comments on this paper. None of these people are to be blamed for my thoughts, but I hope I faithfully transcribed some of their thoughts.