| Willy Brandt School of Public Policy

Capturing Social Processes: Trajectory-Based Qualitative Comparative Analysis

In their virtual Brandt School guest talk on June 23, 2021, Prof. Lasse Gerrits of the Erasmus University Rotterdam and Dr. Sofia Pagliarin of the University of Bamberg presented 'Trajectory-Based Qualitative Comparative Analysis (TJ-QCA)' as an approach that allows the incorporation of time in QCA. The guest talk was part of the “Qualitative Comparative Analysis” course led by PD Dr. Patrick A. Mello.

Despite attempts to make Qualitative Comparative Analysis (QCA) more time-sensitive, current approaches typically do not consider changes of individual cases over time. In the realm of urban renewal projects, where dynamic processes are observed over time, such a static perspective can pose a limitation. In their virtual Brandt School guest talk on June 23, 2021, Prof. Lasse Gerrits of the Erasmus University Rotterdam and Dr. Sofia Pagliarin of the University of Bamberg presented Trajectory-Based Qualitative Comparative Analysis (TJ-QCA) as an approach that allows the incorporation of time in QCA. TJ-QCA’s core property is that configurations are conceptualized dynamically and that researchers use qualitative data to determine case-specific development stages. Consequently, the truth table is also dynamic. The guest talk was part of the “Qualitative Comparative Analysis” course led by PD Dr. Patrick A. Mello.

In their well-attended virtual guest talk, Dr. Gerrits and Dr. Pagliarin illustrated their novel approach drawing on a research project on urban transformations in cities across Germany, Austria, and Switzerland. Using data sources such as newspaper articles and policy reports, they subdivided each urban renewal process into different stages (for example, from the site identification stage to formal planning). They looked at conditions such as civil influence, governance constellation, external shocks, “strategicness”, and urban transition. They showed that TJ-QCA is capable to integrate time dynamics in QCA and that it can capture cross-case as well as within-case variation. Crucially, this rests on researchers using their in-depth knowledge of the cases to define the entailed development stages. This also poses a limitation, in that intensive case knowledge is required to define temporal stages in a meaningful manner (and the definition of development stages always remains open to reinterpretation). That said, TJ-QCA is a promising new approach for comparative methods that should make for interesting developments in the coming years.

~ summary written by Brandt School student Sarah Filippi-Field ~