The Distinctiveness of Comparative Research

Social research is inherently comparative (Lieberson, 1985). Researchers compare the relative effects of variables across cases; they compare cases directly with one another; and they compare empirical cases with counterfactual cases. But the comparative method – sometimes referred to as ‘smallN comparison’ – constitutes a distinctive approach to understanding social phenomena. Frequently, comparative methods are portrayed as a ‘bridge’ between qualitative, case-oriented research and quantitative, variable-oriented research. This interpretation is certainly valid. By embracing aspects of both qualitative and quantitative methods, comparative methods can circumvent some of the limitations of both approaches. But comparative research is not merely a bridge, for it has many distinctive features and strengths. We begin this chapter by reviewing the conventional view of comparative methods as simultaneously qualitative and quantitative. The moderate number of cases employed by comparative researchers allows them to engage in the development, testing, and revision of theory – traditionally the province of case-oriented research, as well as hypothesis testing and theory adjudication – usually seen as the province of variableoriented research. But the greatest strengths of comparative methodology arise from its distinctiveness. Fundamentally set theoretic in nature, comparative methods presuppose particular epistemological and theoretical perspectives (Ragin, 1987; 2000; Rubinson and Ragin, 2007). Although social researchers conventionally conceive of social reality in terms of tendencies and probabilities, social scientific theory – like comparative research – is predominately set theoretic in nature. Frequently, however, even comparative researchers do not recognize the set theoretic character of their work. In the second part of this chapter, we explicate the set theoretic nature of a number of classic comparative studies. We identify and illustrate three types of set theoretic relationships and discuss how they form the basis of three forms of comparative analysis: descriptive, constitutive, and causal. Next, we discuss the case-oriented nature of social research. 1