Peace data: Concept, measurement, patterns, and research agenda

This data article reviews the revised “peace data,” describing the motivations behind them and offering a general description of the different peace scale levels—severe rivalry, lesser rivalry, negative peace, warm peace, and security community respectively. A brief overview of the evolution of peace and rivalry for the 1900–2015 period is presented. Peace in the international system has increased over time, with a decline in rivalries and an increase in security communities being the most notable findings. The article concludes with a discussion of how the peace data might be used to address new questions in international relations research or reconfigure existing ones.