Classification of political regimes as democracy and dictatorship. Classification of democracies as parliamentary, semi-presidential (mixed) and presidential. Classification of dictatorships as military, civilian and royal. Coverage: 202 countries, from 1946 or year of independence to 2008.
Cheibub, José Antonio, Jennifer Gandhi, and James Raymond Vreeland. 2010. “Democracy and Dictatorship Revisited.” Public Choice, vol. 143, no. 2-1, pp. 67-101.