polity data series

{{Short description|Political science project ranking states by democraticity}}

{{pp-pc1}}

{{pp-pc}}{{for|overview of democracy indices | Democracy indices}}

File:Number of nations 1800-2003 scoring 8 or higher on Polity IV scale.png

File:Polity IV 2017.png

The Polity data series is a data series in political science research.{{cite journal |last1=Casper |first1=Gretchen |first2=Claudiu |last2=Tufis |year=2003 |title=Correlation Versus Interchangeability: the Limited Robustness of Empirical Finding on Democracy Using Highly Correlated Data Sets |journal=Political Analysis |volume=11 |issue=2 |pages=196–203|doi=10.1093/pan/mpg009 }}{{Cite web|title=Despite global concerns about democracy, more than half of countries are democratic|url=https://www.pewresearch.org/fact-tank/2019/05/14/more-than-half-of-countries-are-democratic/|access-date=2021-07-16|website=Pew Research Center|language=en-US}}{{Cite web|last=Hensel|first=Paul R.|date=2010|title=Review of Available Data Sets|url=https://oxfordre.com/internationalstudies/view/10.1093/acrefore/9780190846626.001.0001/acrefore-9780190846626-e-418|access-date=2021-07-16|website=Oxford Research Encyclopedia of International Studies|language=en|doi=10.1093/acrefore/9780190846626.013.418|isbn=978-0-19-084662-6}} Along with the V-Dem Democracy Indices project and The Economist Democracy Index, Polity is among prominent datasets that measure democracy and autocracy.{{Cite journal|last=Högström|first=John|date=2013|title=Does the Choice of Democracy Measure Matter? Comparisons between the Two Leading Democracy Indices, Freedom House and Polity IV|url=https://www.cambridge.org/core/journals/government-and-opposition/article/abs/does-the-choice-of-democracy-measure-matter-comparisons-between-the-two-leading-democracy-indices-freedom-house-and-polity-iv/DB07F0A22302905418D0C8AC3D731914|journal=Government and Opposition|language=en|volume=48|issue=2|pages=201–221|doi=10.1017/gov.2012.10|s2cid=19290786|issn=0017-257X}}{{Cite journal|last1=Coppedge|first1=Michael|last2=Lindberg|first2=Staffan|last3=Skaaning|first3=Svend-Erik|last4=Teorell|first4=Jan|date=2016|title=Measuring high level democratic principles using the V-Dem data|url=https://www.jstor.org/stable/26556873|journal=International Political Science Review|volume=37|issue=5|pages=580–593|doi=10.1177/0192512115622046|jstor=26556873|hdl=2077/38971|s2cid=142135251|issn=0192-5121|hdl-access=free}}{{Cite journal|last1=Pelke|first1=Lars|last2=Croissant|first2=Aurel|date=2021|title=Conceptualizing and Measuring Autocratization Episodes|journal=Swiss Political Science Review|language=en|volume=27|issue=2|pages=434–448|doi=10.1111/spsr.12437|issn=1662-6370|doi-access=free}}{{Cite journal|last=Vaccaro|first=Andrea|date=2021-03-16|title=Comparing measures of democracy: statistical properties, convergence, and interchangeability|journal=European Political Science|volume=20|issue=4|pages=666–684|language=en|doi=10.1057/s41304-021-00328-8|issn=1682-0983|doi-access=free}}{{Cite journal|last=Boese|first=Vanessa A|date=2019-06-01|title=How (not) to measure democracy|url=https://doi.org/10.1177/2233865918815571|journal=International Area Studies Review|language=en|volume=22|issue=2|pages=95–127|doi=10.1177/2233865918815571|s2cid=191935546|issn=2233-8659|url-access=subscription}}

The Polity study was initiated in the late 1960s by Ted Robert Gurr and is now continued by Monty G. Marshall, one of Gurr's students. It was sponsored by the Political Instability Task Force (PITF) until February 2020.{{Cite web|date=2021|title=Polity|url=http://www.systemicpeace.org/|url-status=live|archive-url=https://archive.today/20210126202329/http://www.systemicpeace.org/ |archive-date=2021-01-26|access-date=16 July 2021|website=Polity}} The PITF is funded by the Central Intelligence Agency.[http://www.systemicpeace.org/polity/Canada2010.pdf Polity IV Country Report 2010: Canada]{{fcn|date=April 2025}}

The data series has been criticized for its methodology, Americentrism, and connections to the CIA. Seva Gunitsky, an assistant professor at the University of Toronto, stated that the data series was appropriate "for research that examines constraints on governing elites, but not for studying the expansion of suffrage over the nineteenth century".