Original article: Shadow Cases in Comparative Research

Scholars conducting small-N research often deploy ancillary or peripheral cases that are intended to evaluate the more general validity of the findings of their core case studies. Yet we lack a clear set of methodological guidelines for these ancillary cases.2 Drawing on scholarship in the comparative politics subfield for examples, I identify two broad approaches to ancillary cases—the case illustration and the shadow case study. The case illustration, which consists of showing that outcomes in additional cases match what we expect given theory generated from the core case and the values of independent variables in those additional cases, is widely used to evaluate the generality of findings. Part One of the paper argues that this common practice is not as analytically valuable as it could be. I show that the case illustration approach faces challenges to both external and internal validity and propose a larger-N alternative to assessing claims of generality instead.