“…As for large N observational studies, the methodological approach used has so far been an a priori one following methodological needs rather than theoretical guidance. The researcher identifies a dimension which is as externally valid as possible, for instance more regulation v. less regulation or the level of support for a proposal, and, then, he or she either implicitly (Bernhagen, 2012, Bernhagen et al, 2014Costa et al, 2014) or explicitly (Klüver, 2011(Klüver, , 2013Yackee and Yackee, An a priori methodological approach to dimensionality bears a major issue: the justification of dimensions in terms of exhaustiveness (Benoit and Laver, 2012). In other words, by using an a priori methodology the researcher cannot know whether the dimensions selected are exhaustive.…”