The Polity project is one of the most widely used data resources for studying regime change and the effects of regime authority. Polity5 Project, Political Regime Characteristics and Transitions, 1800-2018, annual, cross-national, time-series and polity-case formats coding democratic and autocratic ''patterns of authority'' and regime changes in all independent countries with a total population greater than 500,000 in 2018 (167 countries in 2018).

**Last updated by source:** 2023-03-31

Dataset type: |
Time-Series |

Dataset level: |
Country |

(Marshall & Gurr,
2020)

• Marshall, M. G., & Gurr, T. R. (2020).
*Polity v project, political regime characteristics and transitions,
1800-2018*. Center for Systemic Peace.

Regime Durability: The number of years since the most recent regime change (defined by a three point change in the p_polity score over a period of three years or less) or the end of a transition period defined by the lack of stable political institutions (denoted by a standardized authority score). In calculating the p_durable value, the first year during which a new (post-change) polity is established is coded as the baseline ``year zero'' (value = 0) and each subsequent year adds one to the value of the p_durable variable consecutively until a new regime change or transition period occurs.

More about this variableRevised Combined Polity Score: The polity score is computed by subtracting the p_autoc score from the p_democ score; the resulting unified polity scale ranges from +10 (strongly democratic) to -10 (strongly autocratic). The revised version of the polity variable is designed to facilitate the use of the polity regime measure in time-series analyses. It modifies the combined annual polity score by applying a simple treatment, or 'fix' to convert instances of 'standardized authority scores' (i.e., -66, -77, and -88) to conventional polity scores (i.e., within the range, -10 to +10). The values have been converted according to the following rule set: (-66) Cases of foreign 'interruption' are treated as 'system missing.' (-77) Cases of 'interregnum', or anarchy, are converted to a 'neutral' Polity score of '0.' (-88) Cases of 'transition' are prorated across the span of the transition. For example, country X has a p_polity score of -7 in 1957, followed by three years of -88 and, finally, a score of +5 in 1961. The change (+12) would be prorated over the intervening three years at a rate of per year, so that the converted scores would be as follow: 1957 -7; 1958 -4; 1959 -1; 1960 +2; and 1961 +5.

More about this variable