The Relevance of Mechanistic Evidence in Case-Study Research Attilia Ruzzene – doctoral student Erasmus Institute for Philosophy and Economics

The hypothesis Methods of causal inference, when employed jointly, can play different and mutually supportive roles: they provide evidence that is complementary and can be fruitfully integrated for the task of interest, such as explanation

In case-study research... Scientists develop historical narratives to explain single outcomes such as the outbreak of wars, economic downturns, social revolutions and so forth. The integration of causal evidence obtained through different methods helps researchers structure the causal backbone of the historical narrative.

My case study is: Saxenian 1994: Regional advantage. Culture and Competition in Silicon Valley and Route 128. Explanandum: difference in the economic success the two regions attain Explanans: causal sequence of events that led S.V. to thrive and Route 128 to decline

The causal evidence: To be able to articulate a historical narrative Saxenian employs the small-n method of comparison and the method of process-tracing jointly How are these methods applied? And what type of causal evidence do they deliver?

My analysis: The two methods provide causal evidence that is different and complementary: The small-n method of comparison detects the factor responsible for the outcome: Industrial SystemEconomic Success

on the other hand... Process-tracing identifies the mechanism connecting the causal factor to the outcome How? First, sequences of type-like events that regularly follow one another and are similar in the two regions are detected. Regularities are clue to a single causal mechanism in Silicon Valley and Route 128

The mechanism includes both micro and macro variables causally related so as to connect the causal factor to the outcome is circular: it conveys the causal message from input conditions to output conditions; and from output conditions back to input conditions

Concluding: The small-n method and process-tracing provide evidence that is complementary and jointly structure the backbone of the historical narrative: the former identifies the causal factor; in so doing, it gives the enquiry a start and the narrative its point of departure

Concluding... Process-tracing identifies the causal mechanism; in so doing, it confers causal order The narrative mirrors the circularity of the mechanism: it suggests that events unfold over time on behalf of the causal message moving back and forth through the mechanism