Database of Political Institutions (DPI) 2023政治制度数据库 (DPI) 2023

The Database of Political Institutions (DPI) 2023 compiles cross-national data on the structure and performance of political institutions for about 180 countries, 1975-2023. Each row is a country-year. This extract surfaces eight core governance indicators: checks and balances (CHECKS, number of veto players), government stability (STABS, based on veto-player turnover), party-system polarization (POLARIZ, 0-1), the Herfindahl concentration of government (HERFGOV) and opposition (HERFOPP) legislative seat shares, legislative fractionalization (FRAC, effective number of parties), and two electoral-system dummies (PR, plurality). Source missing code -999 is coded as null. Definitions per Cruz, Keefer, Scartascini & Simpser (2025), DPI Codebook.

政治制度数据库（DPI）2023 版收录约 180 个国家、1975-2023 年的政治制度结构与绩效跨国数据，每行代表一个国家-年。本提取保留八项核心治理指标：制衡程度（CHECKS，否决者数量）、政府稳定性（STABS，基于否决者更替）、政党体系极化（POLARIZ，0-1）、政府与反对派席位份额的赫芬达尔集中度（HERFGOV / HERFOPP）、立法碎片度（FRAC，有效政党数），以及两个选举制度哑变量（PR 比例代表制、pluralty 多数制）。源数据缺失码 -999 已转为 null。定义参见 Cruz, Keefer, Scartascini & Simpser (2025) DPI Codebook。