This box introduces a new quantitative methodology to evaluate alternative scenarios around the Eurosystem/ECB staff baseline projections, with a focus on their empirical plausibility. In a first step, the methodology constructs joint predictive distributions capturing temporal and cross-variable dynamics for euro area real GDP growth and HICP inflation. It then assesses the empirical plausibility of scenario outcomes by computing the likelihood of each scenario relative to that of the baseline against historical patterns. Applied to the Middle East scenarios in the September 2026 ECB staff…