Unified Democracy Scores Introduction Democracy Scores Other Estimates Replication Example Analysis Contact

Project Description

Democracy is a fundamental concept of politics and plays a key role in a variety of theories, informing our understanding topics ranging from economic development to interstate war. Yet, like many constructs in the social sciences, it is unobservable and poses difficult measurement problems for quantitative analysts. This website contains the Unified Democracy Scores (UDS), a set of measures that leverage the efforts of a variety of experts to provide a composite scale of democracy, accompanied by estimates of measurement uncertainty. The UDS were developed by James Melton (University College London), Stephen Meserve (Texas Tech University), and Daniel Pemstein (North Dakota State University). The scores are available for virtually every country in the world from 1946 through 2012.

The UDS are estimated using a Bayesian statistical measurement model and, therefore, can be used to make probabilistic statements about other useful quantities, such as the difference in democracy levels between two countries in a given year. Furthermore, the modeling process produces a number of estimates that make possible the direct comparison of pre-existing scales. This example analysis demonstrates how to most effectively use the UDS in applied work.

This article, which was published in the Autumn 2010 issue of Political Analysis, provides an extended explanation of the UDS and the process we used to generate them.


Most recent release: March 12, 2014