Testing Your Rivals: A Case Selection Framework for Testing Competing Hypotheses

• In Event: Innovations in Case Study Methods

Abstract

When scholars discuss the value of process tracing or case study research, they focus a great deal on how these methods are intrinsically well-suited to adjudicating among competing explanations. Yet, when these same scholars talk about case selection, few account for the fact that we are often coming into an analysis with more than one possible story. Notwithstanding the existing host of constraints on choosing cases, the fact remains that existing case selection frameworks remain largely silent on the matter of testing competing hypotheses and how case selection affects our capacity for inference. Drawing on previous work in process tracing concerning the variety of relationships that exist among competing hypotheses, this paper serves a twofold purpose. First, we evaluate existing case selection methods in terms of their capacity to yield reliable inferences about competing hypotheses. Taking into account the variety of possible relationships among competing hypotheses reveals that although each case selection strategy looks like a single technique, there are in fact multiple permutations within each strategy that are a function of both the relationship among hypotheses and other considerations about each theory individually. In some cases, the relationships among rivals framework upends existing advice; in others, it merely adds a new, but vital consideration for scholars to take into account when engaging in and discussing their case selection. The second objective of the paper is to synthesize existing case selection strategies into a cohesive framework aimed at maximizing our inferential leverage as we test competing hypotheses within one, two, or multiple cases.

Authors

• Sherry Zaks, Stanford University – CISAC

• Melissa Anne Carlson, University of California, Berkeley