Banks Cross-National Time-Series (CNTS) Data Archive--The Banks CNTS Data Archive is a very comprehensive collection of political, economic, and demographic variables, including regime type, legislative effectiveness, the nature of the executive, and cabinet size. Depending on the country and variable, the data go back to 1815. A version covering the years 1815-1997 is available from the Data Center here. To access a more recent version of the dataset with coverage through 2015, please contact the Data Center staff.
Bureaucratic Structure and Economic Performance--This site houses data and documentation for a project by James E. Rauch and Peter B. Evans on bureaucratic quality and structure and "meritocracy" in 35 developing countries.
Cingranelli and Richards (CIRI) Human Rights Dataset--The CIRI Human Rights Dataset contains data on government practices with regard to human rights, including variables on torture, religious freedom, "disappearances," and workers' rights. The data cover the years 1981-2011. While registration is required to access the data, the registration is free.
Comparative Political Data Sets (CPDS)--The CPDS were produced by scholars at the University of Berne. They are similar to the Database of Political Institutions dataset (see below) but focus on OECD countries and post-communist countries and have more emphasis on demographics, electoral results, and ideological compositions of governments. Related datasets are also available for post-communist countries and for countries that are members of the OECD and/or the European Union. Please note the authors' preferred citation format.
Comparative Welfare States Data Set (CWSDS)--The CWSDS is a joint effort by comparative welfare-state scholars such as Evelyne Huber, Charles Ragin, John D. Stephens, and Duane Swank. The data cover 18 OECD countries from 1960 onwards and include many economic, political, and policy variables, including the structure of political institutions and of wage-bargaining institutions.
Database of Political Institutions--This database was put together in part by Phillip Keefer at the World Bank and provides data on the political institutions and structures of different countries in the world from 1975 to 2012. The data are also available here, with coverage up through 2015. Please note the authors' preferred format for citing their data.
"Democracy Indicators Cross-national Time-Series Dataset"--This dataset was compiled by Professor Pippa Norris at Harvard's Kennedy School of Government and contains various measures of democratic government from sources such as Freedom House and Polity IV (referenced elsewhere on this page). The documentation identifies the sources for the variables; users need to consult those sources for more information. In addition to the time-series dataset, Dr. Norris has also compiled a "Shared Global Indicators Cross-national Database" which is also available at this site.
"Democratic Electoral Systems Around the World"--This collection compiled by Matthew Golder provides data for "some of the more important electoral institutions used in all legislative and presidential elections during democratic periods in 199 countries between 1946 (or independence) and 2000 (...) The dataset covers a wide range of institutional features including regime type, the electoral formula, the average and median district magnitude, the number of constituencies and upper tier seats, assembly size etc." The data were recently updated to provide coverage up through 2011. The data are also available via Golder's DataVerse.
Freedom House--Freedom House's annual Freedom in the World reports score countries on a 1-7 scale for both politcal rights and civil liberties. Users can download Freedom Houses' annual rankings via an Excel file with data going back to 1972; go to "Reports" and then choose "Freedom in the World."
Institutions and Elections Project Dataset (IAEP)--The IAEP, which now finds its home at Håvard Hegre, contains data on political institutions for both democratic and non-democratic states. The data cover the period 1972-2012 and measure institutions such as legislatures, executives, judiciaries, central banks, and electoral systems. The data were originally housed at SUNY-Binghamton.
International Human Rights Studies Center (IHRSC) (via the Internet Archive)--The IHRSC at the University of North Texas hosts Steven Poe and Neal Tate's much-cited human-rights datasets. The data and documentation are available for free.
Inter-Parliamentary Union (IPU)--The IPU website contains much information about both national and supranational parliaments. The PARLINE database includes general information on the structure of parliaments (e.g. chambers, constituencies, electoral systems, political mandates). The IPU also provides data on female representation in national parliaments from the late 1990's onwards.
Measures of Democracy 1810-2012--The Polyarchy Dataset was compiled by Tatu Vanhanen and scores countries on political competition, political participation, and an overall democracy index. The data coverage is from 1810 to 2012. See "The Polyarchy Dataset" for an earlier version of these data.
Political Constraint Index (POLCON) Dataset--The POLCON dataset is managed by Professor Witold Henisz at the Wharton School of Management. The dataset measures political constraints on the executive in the form of multiple political actors (e.g. legislative chambers, courts). The dataset and codebook are downloadable upon provision of contact details.
Political Database of the Americas (PDA)--The PDA's data holdings are mainly for elections, but the site also has information on local governance and decentralization, political parties, and executive, legislative, and judicial institutions for the countries of North, Central, and South America.
Political Particularism Around the World--This dataset contains cross-sectional time-series data on electoral systems and the extent to which they create incentives for politicians to cater to "particularlistic" interests. An earlier edition of the data is available via the Inter-American Development Bank.
Political Risk Services (PRS) Group Risk Data--The Data Center's holdings include data resources from the PRS Group and other sources that measure "risk" in the form of political (in)stability and institutional quality (e.g. levels of corruption).
Political Terror Scale (PTS)--Mark Gibney at UNC-Asheville has created a 5-point "political terror scale" that codes countries on human-rights conditions and the rule of law, based on reports from Amnesty International and the U.S. State Department. The data cover the years 1976-2014 and are available for downloading.
Polity IV Project Homepage--The Polity Project data contain information on regime type and political structures (e.g. constraints on executive power, competitiveness of political participation) of states since 1800. Registration is required to access the data.
Preliminary References in EC Law--This dataset was compiled by Alec Stone Sweet and Thomas L. Burnell and contains information on all the preliminary references filed with the European Court of Justice from 1961 to 2006. The data and documentation are also available here and here.
Quality of Government (QOG) Institute--The QOG Institute is hosted by members of the Department of Political Science at Göteborg University in Sweden and is devoted to "the causes, consequences and nature of 'good governance.'" The Institute has created four collections of data on governance: a broad collection of governance indicators that is global in coverage; a more narrow collection that focuses on social policy in wealthier countries; data from expert surveys on politicization and professionalization of public administration in individual countries, and a new data collection on perceptions of corruption in individual regions within EU members. The data are compiled from multiple sources, including the Polity IV Project, the Cingarelli-Richards Human Rights Data, Transparency International, Freedom House, various international organizations, and datasets produced by various academics. The QoG data are available in SPSS, Stata, and comma-delimited (.csv) formats.
State Failure Dataset--The Political Instability Task Force (formerly at George Mason University) has compiled datasets with variables on ethnic wars, revolutionary wars, genocide, "politocide," and regime change in 96 countries for the years 1955-2014.
Transparency International--TransparencyInternational ranks countries based on perceived levels of corruption and publishes those rankings in annual reports. The reports also include rankings on the propensity of firms in different industrialized countries to bribe officials in developing countries. The reports are in .pdf format and go back to 1995. Transparency International's data are also accessible via the Internet Center for Corruption Research.
World Bank Actionable Governance Indicators (AGI) Data Portal--The AGI data portal brings together hundreds of governance-related indicators from multiple data sources and makes them available via tools for downloading and visualization. See https://www.agidata.org/Site/Sources.aspx for a full list of available indicators and data.
World Bank Governance Data--The World Bank hosts a website devoted to data on governance and institutional quality and their relevance for economic development and performance. In addition to the main data page, the Bank also has a web inventory of data pertaining to institutional quality.
World Bank Public Sector Governance--This World Bank site provides a variety of data and non-data resources relevant for the study of institutions, including a list of indicators of governance and institutional quality. This site also has a page devoted to decentralization that includes a cross-national time-series dataset on measures of fiscal decentralization.
World Bank Institute Governance Indicators--This dataset covers 200 countries from 1996-2014, biannually for 1996-2002 and annually afterwards. The six governance indicators include government effectiveness, rule of law, and political stability. The data and rescaled data from their underlying sources are also available at http://info.worldbank.org/governance/wgi/index.aspx.
World Governance Assessment (WGA)--The WGA project focuses on governance and institutional quality as they pertain to development in less-developed countries. The project includes a dataset derived from surveys conducted in 30 LDC's in 1996 and 2000. The dataset contains variables measuring transparency, accountability, participation, and efficiency in six government arenas - civil society, political society, government, bureaucracy, the judiciary, and economic society.