Variance decomposition and cross-country dispersion analysis for the EU-27 founding cohort. This page identifies the structural axes that drive the most inter-country divergence in concentration profiles.
Defense and Logistics together account for 76% of cross-country variance in the EU-27 cohort.
This means that the structural differences between EU member states are overwhelmingly determined by how concentrated their defense and logistics supply chains are, rather than by the other four axes.
Cohort Mean
0.3444
Moderately Concentrated
Median
0.3403
50th percentile
Std Deviation
0.0699
Cross-country dispersion
Countries
27
With valid composites
Highest Axis
Defense
Mean: 0.5732
Lowest Axis
Financial
Mean: 0.1480
Each axis's contribution to total cross-country variance. Variance is computed as the population variance of per-country scores for each axis.
| Axis | Variance | Share of Total | Visual |
|---|---|---|---|
| Defense | 0.050922 | 45.0% | |
| Logistics | 0.034748 | 30.7% | |
| Critical Inputs | 0.014841 | 13.1% | |
| Technology | 0.008947 | 7.9% | |
| Energy | 0.002295 | 2.0% | |
| Financial | 0.001390 | 1.2% |
Mean axis scores and standard deviations across 27 EU-27 member states.
Top 5 countries by composite ISI score.
Bottom 5 countries by composite ISI score.
Variance decomposition is computed as the population variance of per-country axis scores for each of the six ISI dimensions. Each axis's share is its individual variance divided by the sum of all six axis variances.
This is a descriptive decomposition — it identifies which axes account for the most cross-country dispersion, not a causal model. The high concentration of variance in defense and logistics reflects the structural heterogeneity of EU member states in these domains.
Drazsky, S., & International Sovereignty Institute. (2026). International Sovereignty Index (ISI) — EU-27 Founding Cohort (v1.0). Zenodo. https://doi.org/10.5281/zenodo.18764170