Immigration policy openness — work visas, family reunification, asylum processing, border enforcement posture.
General government spending as share of GDP, excluding transfers already captured under fiscal.transfer_expansion to avoid double-counting.
Joint EU-Turkey Statement of 18 March 2016 substantially negotiated by Chancellor Merkel and PM Davutoğlu: Turkey to take back all irregular migrants crossing to Greek islands; 'one-for-one' Syrian resettlement from Turkey to EU; €6bn Facility for Refugees in Turkey (€3bn + €3bn); visa-liberalisation roadmap; accession-talks reopening. Aegean arrivals fell from ~850k in 2015 to ~175k in 2016 and ~42k in 2017. Legal status of the instrument contested (EU General Court ruled in 2017 it was not an EU act).
Per invariant 3, reforms are scored by what they did on each channel-separated axis, not by the party that enacted them. This fingerprint is how the policy-match engine finds historical analogues.
Explicit links are curated by the author. Inferred links are hypotheses in the library that test the same axes this policy moved — the framework's answer to "what does the data say about a policy like this?".
Ranked by axis-fingerprint overlap with this policy. Direction match bolded — those are the closest historical analogues. Shape of the match is what drives policy-outcome comparison, not the country or party label.