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	Foreign Policy Similarity Score	Democratic Peace Analysis
Field	International Relations	International Relations
Family	Process / pipeline	Process / pipeline
Year of origin	2011	1993
Originator	Foreign-policy-similarity literature (Signorino & Ritter; Voeten ideal points; Frank Häge chance correction)	Zeev Maoz & Bruce Russett (and the broader democratic-peace literature)
Type	Dyadic measurement of revealed foreign-policy agreement	Observational dyadic test of the regime-type/conflict relationship
Seminal source	Häge, F. M. (2011). Choice or circumstance? Adjusting measures of foreign policy similarity for chance agreement. Political Analysis, 19(3), 287–305.	Maoz, Z., & Russett, B. (1993). Normative and structural causes of democratic peace, 1946–1986. American Political Science Review, 87(3), 624–638.
Aliases	Foreign Policy Similarity Measurement, UN Voting Affinity Score, Ideal Point Distance, State Preference Similarity	Democratic Peace Theory Testing, Dyadic Democratic Peace Analysis, Joint Democracy and Conflict Analysis, Liberal Peace Analysis
Related	3	3
Summary	A foreign-policy similarity score measures how alike two states' revealed foreign-policy positions are — most commonly from their votes in the UN General Assembly, but also from alliance portfolios or treaty positions. It is a workhorse measure of shared interests, affinity, and alignment in dyadic IR. Häge (2011) shows that naive agreement and the popular S-score can be inflated by chance agreement that arises because states differ in how often they take each position, and proposes chance-corrected indices (Scott's π, Cohen's κ) that better isolate genuine alignment.	Democratic peace analysis is the empirical study of the proposition that democracies rarely or never fight one another. Building on the dyadic research design crystallized by Maoz and Russett (1993), it codes the regime type of each state, constructs dyad-years, and models the probability of militarized conflict as a function of joint democracy alongside controls for power, contiguity, alliances, and trade. The approach has produced one of the most robust empirical regularities in international relations and a long debate over whether shared norms or institutional structures account for it.