In search of the worlds of compliance: promises and pitfalls of quantitative testing

The “worlds of compliance” typology as developed by Falkner/Treib/Hartlapp/Leiber (2005) builds on ideal-typical procedural modes of domestic adaptation to EU directives. Recently, the Journal of European Public Policy (JEPP) has published an interesting article discussing this concept. At closer inspection, the analysis presented by Dimiter Toshkov results in some
support for, but also some criticism of, the worlds of compliance. His statistics-based approach gives us the opportunity to raise several issues of crucial importance for the entire scholarly community in the field of EU implementation research. Among these are the
problem of choosing adequate indicators, of using reliable quantitative data, and of appropriately applying domestic politics approaches and veto player theory. These
discussions are of general interest also for a very practical reason: similar methodological choices are rather common in current European integration research.