My research interests include conflict and cooperation, democratization, and spatial dimensions of social and political processes. I am the author of All International Politics is Local: The Diffusion of Conflict, Integration, and Democratization (University of Michigan Press, 2002), Spatial Regression Models (Sage, 2018, with Michael D. Ward), Inequality, Grievances, and Civil War (Cambridge University Press, 2013, with Lars-Erik Cederman and Halvard Buhaug), and journal articles in the American Journal of Political Science, American Political Science Review, Annals of the Association of American Geographers, Biological Reviews, Comparative Political Studies, Conflict and Cooperation, Defence and Peace Economics, Economic History Review, European Journal of International Relations, International Interactions, International Organization, Internasjonal Politikk, International Studies Quarterly,
Journal of Conflict Resolution, Journal of Peace Research, Journal of Politics, PLOS One,
Political Analysis, Political Psychology, R Journal, and World Politics.