Differentiated integration approach and EU migration policy: A statistical analysis

This thesis aims to demonstrate that the migration policies of the European Union (EU) member states exhibit systematic differentiation rather than homogeneous convergence. The main objective of the study is to analyze the migration management capacity of member states through quantitative methods in order to evaluate both the inclusiveness of EU migration policies and to determine whether the integration process is evolving towards a supranational orientation or, as the New Intergovernmentalism (NI) approach suggests, towards an intergovernmental structure. The rationale for selecting this topic lies in the fact that migration is one of the most contested policy areas of the EU, and understanding how differentiation affects the Union's ideal of integration holds critical importance for both academic literature and policymakers. Accordingly, the first hypothesis of the study posits that EU member states display a differentiated integration model in migration policies, while the second argues that the NI approach provides an effective framework to explain this differentiation. In the study, the migration policies of the 27 EU member states (EU-27) were evaluated across six dimensions based on the United Nations Sustainable Development Goals (SDG) 10.7.2 indicators. These indicators were quantified through the Migration Governance Framework (MiGOF) developed by the International Organization for Migration (IOM). The data were subjected to K-means clustering analysis and One-way ANOVA test in the RStudio program. The analysis revealed that countries are grouped into three categories—high, medium, and low performance—and that statistically significant differentiation exists in five of the six main criteria. Furthermore, systematic violations were identified in the transposition of the Common European Asylum System (CEAS) directives into domestic law; in addition, attitudes toward the Pact on Migration and Asylum confirmed the differentiation between the strong opposition of the Visegrad Group countries and the conditional support of Mediterranean countries. In conclusion, the findings support the core hypotheses of the NI approach and empirically demonstrate that differentiated integration has become a permanent and structural norm in EU migration policies.