Political Terror Scale
The Political Terror Scale (PTS) is one of the most widely used indicators in comparative analyses of human-rights practices. The scale measures the respect for the rights associated with the integrity of the person, and was originally generated by Michael Stohl and David Carleton in the 1980s. Since then, several versions of the Political Terror Scale (PTS) dataset have been made available online, with different geographical and temporal coverage. The latest version of the dataset is maintained by Mark Gibney, Linda Cornett and Reed Wood (University of North Caroline Asheville); the version used in Poe, Tate and Keith (1999) contains data for some years not covered in Gibney’s dataset. However, while Poe, Tate and Keith did much of the coding between 1976-1979 and their name is frequently associated with analysis of these data, the dataset is one single project, now maintained by Gibney et al.
Political Terror Scale Dataset.
Political Terror Scale
Excel, On-screen tables
Data types and sources
Standards-based indicators. Expert coding based on the US State Department’s Country Reports on Human Rights Practices and Amnesty International’s Annual Report.
The PTS dataset consists of two variables, one based on the US State Department’s Country Reports, the other on Amnesty International’s Annual Report. The variables attempt to measure levels of political violence and terror that a country experiences in a particular year based on a 5-level “terror scale” originally developed by Freedom House.
Time coverage and updates
Covers the period 1976-2010. Updated annually. Last update: 2010.
The coding rules are described on the PTS website, and can also be found in Gibney and Dalton (1996), which is available for download from Mark Gibney's website. See also Hathaway and Ho (2004) and McCormick and Mitchell (1997) for critical assessments of the PTS, and Poe, Carey and Vazquez (2001) for an analysis of the difference between the US State Department and Amnesty International human-rights reports. See also the FAQ-section on the project homepage.
Access conditions and cost
Available free of charge.
Data can be downloaded in pre-defined Excel-files. The website also provides an interactive map where data can be viewed.
Data formatsExcel and on-screen tables.
Comparability and data quality
While the PTS is among the most widely used as indicators of human-rights practices it is difficult to measure human rights in a clear and objective manner, and users of the data should be aware that there might be considerable problems of comparability and measurement error. While issues of validity is likely to be present in such a dataset, the advantage of this dataset is that it contains two variables constructed in the same manner, and coded by the same coders for the same years (measures are taken to promote inter-coder reliability, see FAQ). Data users can thus read both reports upon which the indicators are based and choose the one they see best fit, or use both scores and compute an average. See Goldstein (1992), Landman (2004) and Chapter 5 in Rydland et al. (2008) for a more detailed discussion of human-rights indicators in general.
Apodaca, Clair, and Michael Stohl. 1999. “United States human rights policy and foreign assistance”. International Studies Quarterly 43 (1): 185–198.
Carleton, David, and Michael Stohl. 1987. “The role of human rights in US foreign assistance policy: a critique and reappraisal”. American Journal of Political Science 31 (November): 1002-1018.
Gibney, Mark, and Matthew Dalton. 1996. “The Political Terror Scale”. In David L. Cingranelli (ed.): Human Rights and Developing Countries, Greenwich: JAI.
Goldstein, Robert Justin. 1992. “The limitations of using quantitative data in studying human rights abuses”. In Human Rights and Statistics: Getting the Record Straight, eds. Thomas B. Jabine and Richard P. Claude. Philadelphia: University of Pennsylvania Press.
Landman, Todd. 2004. “Measuring human rights: principle, practice, and policy”. Human Rights Quarterly 26 (November): 906-931.
McCormick, James M., and Neil J. Mitchell. 1997. “Human rights violations, umbrella concepts, and empirical analysis”. World Politics 49 (4): 510-525.
Poe, Steven C., Sabine C. Carey and Tanya C. Vazquez. 2001. “How are these pictures different? A quantitative comparison of the US State Department and Amnesty International human rights reports, 1976-1995”. Human Rights Quarterly 23 (August): 650-677.
Poe, Steven C., Neal Tate and Linda Camp Keith. 1999. ”Repression of the human right to personal integrity revisited: a global cross-national study covering the years 1976-1993”. International Studies Quarterly 43 (June): 291–313.
Rydland, Lars Tore, Sveinung Arnesen and Åse Gilje Østensen. 2008. Contextual data for the European Social Survey. An Overview and assessment of extant resources. NSD Report No.124, Norwegian Social Science Data Services (NSD).