Selecting Appropriate Cases When Tracing Causal Mechanisms

Abstract

The last decade has witnessed resurgence in the interest in studying the causal mechanisms linking causes and effects. This article games through the methodological consequences that adopting a systems understanding of mechanisms has for what types of cases we should select when using in-depth case study methods like process tracing. The article proceeds in three steps. We first expose the assumptions that underpin the study of causal mechanisms as systems that have methodological implications for case selection. In particular, we take as our point of departure the case-based position, where: causation is viewed in deterministic and asymmetric terms, the focus is ensuring causal homogeneity in case-based research to enable cross-case inferences to be made, and finally where mechanisms are understood as more than just intervening variables but instead a system of interacting parts that transfers causal forces from causes to outcomes. We then develop a set of case selection guidelines that are in methodological alignment with these underlying assumptions. We then develop guidelines for research where the mechanism is the primary focus, contending that only typical cases where both X, Y, and the requisite contextual conditions are present should be selected. We compare our guidelines with the existing, finding that practices like selecting most/least-likely cases are not compatible with the underlying assumptions of tracing mechanisms. We then present guidelines for deviant cases, focusing on tracing mechanisms until they breakdown as a tool to shed light on omitted contextual and/or causal conditions.

When Epistemic Communities Fail: Exploring the Mechanism of Policy Influence

“…This includes explaining cases of low or no influence, which is what this article intends to do, in line with Cross's (2012) call for a renewal in the epistemic communities research program by inclusion of comparative studies that take into account also negative cases (see also Beach & Pedersen, ; Capoccia & Kelemen, ; Mahoney & Goertz, ; Mikkelsen, ). This text compares a case of successful diffusion of a popular international trend in health policy—the establishment of a health technology assessment (HTA) agency—in Poland, as a result of efforts of the Polish HTA epistemic community, with a negative (deviant) case in the Czech Republic, where despite similar activities of a comparable HTA epistemic community no agency was established.…”

Process-Tracing as a Tool to Analyse Discretion

“…Finally, theories at the level of causal mechanisms are typically sensitive to context. The same cause might link to the same outcome through different mechanisms in different contexts, or the same cause might produce a different outcome through different mechanisms in different contexts (Falleti and Lynch 2009;Beach and Pedersen 2016a;Beach and Rohlfing 2016). By tracing mechanisms in particular cases, we can figure out which mechanism was operating in the case and then compare our findings with results from other cases in different contexts to learn more about the impact of scope conditions on the politics of delegation and discretion.…”

“…In process-tracing, we are not assessing the difference that changes in values of the cause make for values of the outcome across cases. Instead, inferences are made using the correspondence between hypothetical and actual observable manifestations of the operation of mechanisms within a selected case, what can be termed mechanistic, within-case evidence (Beach and Pedersen 2016a;Bennett 2014).…”

“…Yet causes are operative within cases, not across cases (Mahoney 2008;Beach and Pedersen 2016a). This means that if we really want to uncover empirically how a cause produces an outcome, we need to engage in an in-depth within-case analysis instead of merely investigating trends across cases.…”

“…To do so requires that we theorize in a more deterministic fashion. Instead of talking about trends and correlations, we should rather focus on the causal mechanisms that will produce an outcome when the cause(s) and scope conditions required for its operation are present (Beach and Pedersen 2016a).…”