Timing the changes in political structures - A new polity database

This article introduces the Polity IIId (''d'' is for dates) data set . The Polity project codes the precise dates of changes in politi cal struc identified by Polity III for all independent countries in t he international system from 1800 to 1994. By moving from annual measurements of authority and polity characteristics, the Polity md d ata are more appropriate for event-based analysis. The authors di scuss the implications of the new data set for event count and event history models of democracy and war, democratization and war, reg ime type and civil war, and causes of change in political structure