手法を比較

	Polity Score Analysis	Democratic Peace Analysis
分野	International Relations	International Relations
系統	Process / pipeline	Process / pipeline
提唱年	2020	1993
提唱者	Ted Robert Gurr, Monty Marshall & Keith Jaggers (Center for Systemic Peace)	Zeev Maoz & Bruce Russett (and the broader democratic-peace literature)
種類	Composite ordinal measure of regime authority characteristics	Observational dyadic test of the regime-type/conflict relationship
原典	Marshall, M. G., & Gurr, T. R. (2020). Polity5: Political Regime Characteristics and Transitions, 1800–2018 (Dataset Users' Manual). Vienna, VA: Center for Systemic Peace.	Maoz, Z., & Russett, B. (1993). Normative and structural causes of democratic peace, 1946–1986. American Political Science Review, 87(3), 624–638.
別名	Polity IV Analysis, Polity5 Analysis, Polity2 Score, Polity Index of Democracy and Autocracy	Democratic Peace Theory Testing, Dyadic Democratic Peace Analysis, Joint Democracy and Conflict Analysis, Liberal Peace Analysis
関連	3	3
概要	Polity score analysis uses the Polity dataset to measure and compare the regime characteristics of states on a continuum from full autocracy to full democracy. Maintained by the Center for Systemic Peace (Marshall and Gurr), Polity codes institutional features — how chief executives are recruited, the constraints on their authority, and the openness of political competition — into separate democracy and autocracy indices that combine into a single polity score from −10 to +10. It is one of the most widely used measures of regime type in comparative politics and international relations.	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.