John Gerring

What Is a Case Study and What Is It Good for

This paper aims to clarify the meaning, and explain the utility, of the case study method, a method often practiced but little understood. A “case study,” I argue, is best defined as an intensive study of a single unit with an aim to generalize across a larger set of units. Case studies rely on the same sort of covariational evidence utilized in non-case study research. Thus, the case study method is correctly understood as a particular way of defining cases, not a way of analyzing cases or a way of modeling causal relations. I show that this understanding of the subject illuminates some of the persistent ambiguities of case study work, ambiguities that are, to some extent, intrinsic to the enterprise. The travails of the case study within the discipline of political science are also rooted in an insufficient appreciation of the methodological tradeoffs that this method calls forth. This paper presents the familiar contrast between case study and non-case study work as a series of characteristic strengths and weaknesses—affinities—rather than as antagonistic approaches to the empirical world. In the end, the perceived hostility between case study and non-case study research is largely unjustified and, perhaps, deserves to be regarded as a misconception. Indeed, the strongest conclusion to arise from this methodological examination concerns the complementarity of single-unit and cross-unit research designs.

Case Selection Techniques in Case Study Research: A Menu of Qualitative and Quantitative Options

How can scholars select cases from a large universe for in-depth case study analysis? Random sampling is not typically a viable approach when the total number of cases to be selected is small. Hence attention to purposive modes of sampling is needed. Yet, while the existing qualitative literature on case selection offers a wide range of suggestions for case selection, most techniques discussed require in-depth familiarity of each case. Seven case selection procedures are considered, each of which facilitates a different strategy for within-case analysis. The case selection procedures considered focus on typical, diverse, extreme, deviant, influential, most similar, and most different cases. For each case selection procedure, quantitative approaches are discussed that meet the goals of the approach, while still requiring information that can reasonably be gathered for a large number of cases.

Political Institutions and Corruption: The Role of Unitarism and Parliamentarism

A raft of new research on the causes and effects of political corruption has emerged in recent years, in tandem with a separate, growing focus on the effects of political institutions on important outcomes such as economic growth, social equality and political stability. Yet we know little about the possible role of different political institutional arrangements on political corruption. This article examines the impact of territorial sovereignty (unitary or federal) and the composition of the executive (parliamentary or presidential) on levels of perceived political corruption cross-nationally. We find that unitary and parliamentary forms of government help reduce levels of corruption. To explain this result, we explore a series of seven potential causal mechanisms that emerge out of the competing centralist and decentralist theoretical paradigms: (1) openness, transparency and information costs, (2) intergovernmental competition, (3) localism, (4) party competition, (5) decision rules, (6) collective action problems, and (7) public administration. Our empirical findings and our analysis of causal mechanisms suggest that centralized constitutions help foster lower levels of political corruption.

Democracy and Economic Growth: A Historical Perspective

Recent studies appear to show that democracy has no robust association with economic growth. Yet all such work assumes that the causal effect of democracy can be measured by a countrys regime status in a particular year (T), which is correlated with its growth performance in a subsequent period (T+1). The authors argue that democracy must be understood as a stock, rather than a level, measure. That is, a countrys growth performance is affected by the number of years it has been democratic, in addition to the degree of democracy experienced during that period. In this fashion, democracy is reconceptualized as a historical, rather than a contemporary, variable—with the assumption that long-run historical patterns may help scholars to understand present trends. The authors speculate that these secular-historical infiuences operate through four causal pathways, each of which may be understood as a type of capital: physical capital, human capital, social capital, and political capital. This argument is tested in a cross-country analysis and is shown to be robust in a wide variety of specifications and formats.

Is There a (Viable) Crucial-Case Method?

Case study researchers use diverse methods to select their cases, a matter that has elicited considerable comment and no little consternation. Of all these methods, perhaps the most controversial is the crucial-case method, first proposed by Harry Eckstein several decades ago. Since Eckstein’s influential essay, the crucial-case approach has been used in a multitude of studies across several social science disciplines and has come to be recognized as a staple of the case study method. Yet the idea of any single case playing a crucial (or critical) role is not widely accepted. In this article, the method of the crucial case is explored, and a limited defense (somewhat less expansive than that envisioned by Eckstein) of that method is undertaken. A second method of case-selection, closely associated with the logic of the crucial case, is introduced: the pathway case.

Conceptualizing and Measuring Democracy: A New Approach

InthewakeoftheColdWar,democracyhasgainedthestatusofamantra.Yetthereisnoconsensusabouthowtoconceptualizeand measure regimes such that meaningful comparisons can be made through time and across countries. In this prescriptive article, we argueforanewapproachtoconceptualizationandmeasurement.Wefirstreviewsomeoftheweaknessesamongtraditionalapproaches. Wethenlayoutourapproach,whichmaybecharacterizedas historical, multidimensional, disaggregated,and transparent.Weendby reviewing some of the payoffs such an approach might bring to the study of democracy.

Democracy and Human Development

Does democracy improve the quality of life for its citizens? Scholars have long assumed that it does, but recent research has called this orthodoxy into question. This article reviews this body of work, develops a series of causal pathways through which democracy might improve social welfare, and tests two hypotheses: (a) that a country’s level of democracy in a given year affects its level of human development and (b) that its stock of democracy over the past century affects its level of human development. Using infant mortality rates as a core measure of human development, we conduct a series of time-series—cross-national statistical tests of these two hypotheses. We find only slight evidence for the first proposition, but substantial support for the second. Thus, we argue that the best way to think about the relationship between democracy and development is as a time-dependent, historical phenomenon.

The Mechanismic Worldview: Thinking Inside the Box

A widespread turn towards mechanism-centred explanations can be viewed across the social sciences in recent decades. This article clarifies what it might mean in practical terms to adopt a mechanismic view of causation. This simple task of definition turns out to be considerably more difficult than it might at first appear. The body of the article elucidates a series of tensions and conflicts within this ambient concept, looking closely at how influential authors have employed this ubiquitous term. It is discovered that ‘mechanism’ has at least nine distinct meanings as the term is used within contemporary social science: (1) the pathway or process by which an effect is produced; (2) an unobservable causal factor; (3) an easy-to-observe causal factor; (4) a context-dependent (bounded) explanation; (5) a universal (or at least highly general) explanation; (6) an explanation that presumes highly contingent phenomena; (7) an explanation built on phenomena that exhibit lawlike regularities; (8) a distinct technique of analysis (based on qualitative, case study, or process-tracing evidence); or (9) a micro-level explanation for a causal phenomenon. Some of these meanings may be combined into coherent definitions; others are obviously contradictory. It is argued, however, that only the first meaning is consistent with all contemporary usages and with contemporary practices within the social sciences; this is therefore proposed as a minimal (core) definition of the concept. The other meanings are regarded as arguments surrounding the core concept.

Centripetal Democratic Governance: A Theory and Global Inquiry

Why are some democratic governments more successful than others? What impact do various political institutions have on the quality of governance? This paper develops and tests a new theory of democratic governance. This theory, which we label centripetalism, stands in contrast to the dominant paradigm of decentralism. The centripetal theory of governance argues that democratic institutions work best when they are able to reconcile the twin goals of centralized authority and broad inclusion. At the constitutional level, our theory argues that unitary, parliamentary, and list-PR systems (as opposed to decentralized federal, presidential, and nonproportional ones) help promote both authority and inclusion, and therefore better governance outcomes. We test the theory by examining the impact of centripetalism on eight indicators of governance that range across the areas of state capacity, economic policy and performance, and human development. Results are consistent with the theory and robust to a variety of specifications.

Do Neoliberal Policies Deter Political Corruption

This article probes the relationship between neoliberal economic poli- cies and political corruption, focusing in particular on the impact of trade and invest- ment policies, regulatory policy, and the overall size of the public sector on corruption+ Using a large cross-national data set from the mid- to late 1990s, we test the neolib- eral hypotheses that market-oriented economic policies are associated with lower lev- els of political corruption, and state intervention in the economy with higher levels+ Consistent with the neoliberal argument, we find that open trade and investment pol- icies and low, effective regulatory burdens do correlate with lower levels of political corruption+ However, we find no consistent relationship between the aggregate size of the public sector and political corruption+ While the neoliberal hypothesis on polit- ical corruption has initial empirical support, its lessons cannot be applied wholesale+ Market-oriented states may be less corrupt, but interventionist states, as measured by public spending, are not necessarily more corrupt+