Analysing necessity and sufficiency with Qualitative Comparative Analysis: how do results vary as case weights change?
- 551 Downloads
Ragin’s Qualitative Comparative Analysis (QCA) and related set theoretic methods are increasingly popular. This is a welcome development, since it encourages systematic configurational analyses of social phenomena. One downside of this growth in popularity is a tendency for more researchers to use the approach in a formulaic manner—something made possible, and more likely, by the availability of free software. We wish to see QCA employed, as Ragin intended, in a self-critical manner. For this to happen, researchers need to understand more of what is going on behind the results generated by the available software packages. One important aspect of set theoretic analyses of sufficiency and necessity is the effect that the distribution of cases in a dataset can have on results. We explore this issue in a number of ways. We begin by exploring how both deterministic and nondeterministic data-generating processes are reflected in the analyses of populations differing in only the weights of types of cases. We show how and why weights matter in causal analyses that focus on necessity and also, where models are not fully specified, sufficiency. We then draw on this discussion to show that a recent textbook discussion of hidden necessary conditions is weakened as a result of its neglect of weighting issues. Finally, having shown that case weights raise a number of difficulties for set theoretic analyses, we offer suggestions, drawing on two imagined population datasets concerning health outcomes, for mitigating their effect.
KeywordsQualitative Comparative Analysis (QCA) Set theoretic methods Case weights Necessary conditions Sufficient conditions Simulation
This work has been supported by the UK’s Economic and Social Research Council. Thanks to the four Q&Q reviewers for their very helpful comments.
- Baumgartner, M.: Regularity theories reassessed. Philosophia 36, 327–354 (2008)Google Scholar
- Baumgartner, M.: Parsimony and causality. Qual. Quant. (2014). doi: 10.1007/s11135-014-0026-7
- Baumgartner, M., Epple, R.: A coincidence analysis of a causal chain: the Swiss minaret vote. Sociol. Methods Res. 43, 280–312 (2014)Google Scholar
- Bhaskar, R.: A Realist Theory of Science. Harvester, Brighton (1975)Google Scholar
- Bhaskar, R.: The Possibility of Naturalism. Harvester, Brighton (1979)Google Scholar
- Cooper, B.: Applying Ragin’s crisp and fuzzy set QCA to large datasets: social class and educational achievement in the National Child Development Study. Sociol. Res. Online 10(2) (2005). http://www.socresonline.org.uk/10/2/cooper1.html
- Cooper, B., Glaesser, J.: Paradoxes and pitfalls in using fuzzy set QCA: illustrations from a critical review of a study of educational inequality. Sociol. Res. Online 16(3) (2011). http://www.socresonline.org.uk/16/3/8.html
- Cooper, B., Glaesser, J.: Qualitative work and the testing and development of theory: lessons from a study combining cross-case and within-case analysis via Ragin’s QCA. Forum: Qualitative Social Research/Qualitative Sozialforschung. 13(2), Art. 4 (2012). http://www.qualitative-research.net/index.php/fqs/article/view/1776
- Cooper, B., Glaesser, J., Thomson, S.: Schneider and Wagemann’s proposed enhanced standard analysis for Ragin’s Qualitative Comparative Analysis: some unresolved problems and some suggestions for addressing them. COMPASSS WP Series 2014–77 (2014). http://www.compasss.org/wpseries/CooperGlaesserThomson2014.pdf
- Gerring, J.: Social Science Methodology: A Unified Framework, 2nd edn. Cambridge University Press, Cambridge (2012)Google Scholar
- Glaesser, J., Cooper, B.: Gender, parental education, and ability: their interacting roles in predicting GCSE success. Camb. J. Educ. 42(4):463–480 (2012)Google Scholar
- Ragin, C.C.: The Comparative Method. Moving Beyond Qualitative and Quantitative Strategies. University of California Press, Berkeley (1987)Google Scholar
- Ragin, C.C.: Fuzzy-Set Social Science. University of Chicago Press, Chicago (2000)Google Scholar