Democracy-Dictatorship (DD) Revisited — Cheibub, Gandhi & Vreeland民主-独裁分类数据集 (DD/ACLP) — Cheibub, Gandhi & Vreeland

The Democracy-Dictatorship (DD) dataset provides a binary classification of political regimes for 202 countries from 1946 to 2008, based on the seminal work by Przeworski et al. and updated by Cheibub, Gandhi & Vreeland. Regimes are classified as democracies if the executive and legislature are directly elected, there is more than one party, and alternation in power has occurred.

The dataset also distinguishes six regime types: parliamentary, semi-presidential, and presidential democracies; and civilian, military, and royal dictatorships.

民主-独裁（DD）数据集基于 Przeworski 等人的开创性工作，由 Cheibub、Gandhi 和 Vreeland 更新，覆盖 202 个国家 1946–2008 年的政体二分类。若行政和立法机关由直选产生、存在多党且发生过权力交替，则归类为民主政体。

数据集同时区分六种政体类型：议会制、半总统制和总统制民主；文官、军人和王室独裁。