Process-Tracing Methods: Foundations and Guidelines

Chapter 2. The Three Different Variants of Process-Tracing and Their Uses

9 Chapter 2 The Three DifferentVariants of Process-Tracing and Their Uses This chapter develops the argument that there are three different research situations in which process-tracing methods can be used, resulting in three distinct variants of process-tracing. In contrast, the state of the art treats process-tracing as a singular method, resulting in murky methodological guidelines. Whereas most case studies that use process-tracing employ a case-centric variant that we term the explaining-outcome process-tracing, most methodological works prescribe a theory-centric version of processtracing that involves the deductive testing of whether a generalizable mechanism is present in a single case. The dissonance between what we practice and what we preach has resulted in considerable confusion about what good process-tracing is. We contend that clearer prescriptions can be developed when we differentiate process-tracing into three distinct variants. We do not suggest this differentiation for its own sake. These differences have important methodological implications for research design that are masked when we treat process-tracing as a single method. We explore these implications throughout the rest of this book. For example, the three variants differ on key questions such as how causal mechanisms are understood, whether the purpose is to make inferences about whether a mechanism is present in a case or to account for a particular outcome, and whether they can be nested into mixed-method designs. We first summarize the state of the art, showing that existing work on process-tracing treats it as a singular method. We then illustrate that there are three distinct research situations that call for different methodological tools, implying the need to differentiate the method into three distinct variants that reflect these different purposes. We conclude by briefly illustrating 10 Process-Tracing Methods each of the three variants, showing what we are tracing in each of them and how analysis proceeds. 2.1.The State of the Art—One Method In their chapter-length presentation of process-tracing, George and Bennett (2005) mention the range of different forms of process-tracing as they have been used in practice. The authors argue that process-tracing has been used in a variety of ways, including both detailed narratives and case studies, where “at least parts of the narrative are accompanied with explicit causal hypotheses highly specific to the case without, however, employing theoretical variables for this purpose or attempting to extrapolate the case’s explanation into a generalization” (210–11). In other varieties of process-tracing, “the investigator constructs a general explanation rather than a detailed tracing of a causal process” (211). Yet in the rest of their chapter, George and Bennett treat process-tracing as a singular method, masking the differences that relate to the different uses. More recent accounts also treat process-tracing as a single method, often defining it as a deductive tool to test whether causal mechanisms are present and function as theorized. For example Gerring (2007a: 172–85) describes a two-stage deductive research process where the analyst first clarifies the theoretical argument and then empirically verifies each stage of this model. Checkel describes process-tracing as the attempt to “trace the process in a very specific, theoretically informed way. The researcher looks for a series of theoretically predicted intermediate steps” (2008: 363). The end result is a middle-range theory. Bennett describes process-tracing as a method that involves “the examination of ‘diagnostic’ pieces of evidence within a case that contribute to supporting or overturning alternative explanatory hypotheses. A central concern is with sequences and mechanisms in the unfolding of hypothesized causal processes. The research looks for the observable implications of hypothesized explanations. . . . The goal is to establish whether the events or processes within the case fit those predicted by alternative explanations ” (2010: 208). Yet treating process-tracing as a singular method results in a large discrepancy between our prescriptions for good process-tracing (which rely on a relatively deductive variant of process-tracing) and what we do in practice (where many scholars want to use the method either to build theories or to account for particularly puzzling outcomes). The result of treating process- Three Different Variants of Process-Tracing and Their Uses 11 tracing as one method is a set of murky methodological guidelines, along with confused students and practitioners. 2.2.The Three Different Uses of Process-Tracing Methods Process-tracing methods have three distinct research purposes. As illustrated...