Content area
Full text
Despite repeated calls for the use of "mixed methods" in comparative analysis, political scientists have few systematic guides for carrying out such work. This paper details a unified approach which joins intensive case-study analysis with statistical analysis. Not only are the advantages of each approach combined, but also there is a synergistic value to the nested research design: for example, statistical analyses can guide case selection for in-depth research, provide direction for more focused case studies and comparisons, and be used to provide additional tests of hypotheses generated from small-N research. Small-N analyses can be used to assess the plausibility of observed statistical relationships between variables, to generate theoretical insights from outlier and other cases, and to develop better measurement strategies. This integrated strategy improves the prospects of making valid causal inferences in cross-national and other forms of comparative research by drawing on the distinct strengths of two important approaches.
Long-standing methodological debates highlighting inherent tradeoffs in the main modes of comparative analysis have tended to force scholars to choose between one of two imperfect approaches. On the one hand, even while defending its merits, Lijphart (1971, 685) succinctly identified the central shortcoming of the "comparative method" as the problem of "many variables, small number of cases." In the years to follow, some scholars argued that such attempts to draw general conclusions from intensive analysis of one or a few cases have been flawed by various problems of selection bias, lack of systematic procedures, and inattention to rival explanations (e.g., Achen and Snidal 1989; Geddes 1990; King, Keohane, and Verba 1994). Alternatively, other scholars have argued not only that some of the critiques of qualitative research may be overdrawn and the contributions of these works underappreciated, but also that the complex phenomena and causal processes associated with big, national-level outcomes require a more close-range analytic tool that is less likely to generate spurious results (e.g., Collier, Brady, and Seawright 2004; Collier and Mahoney 1996; Munck 1998; Rogowski 1995). Qualitatively oriented scholars have their own tradition of challenging the statistical approach, including Sartori's (1970) powerful invective against "conceptual stretching," which in turn has been refuted by scholars such as Jackman (1985), who argues that the comparative method is a "weak approximation of the statistical method,"...