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Ornithology and Varieties of Conflict: A Personal Retrospective on Conflict Forecasting

Kristian Skrede Gleditsch ORCID logo


This note provides a retrospective on lessons learned in research on conflict forecasting, motivated by reflections around the retirement of Professor Michael D. Ward from Duke University. I argue that an excessive focus on “black swans” or surprising events that are hard to forecast detracts from considering the more frequent “white swans” or regularities in conflict. It is often more useful to focus on modal conflicts than exceptions, and substantial progress has been made in recent research. I identify some key lessons learned and highlight the need for researchers to distinguish between features that are more or less difficult to forecast.


Beck, N., King, G. & Zeng, L. (2000). Improving quantitative studies of international conflict: a conjecture. American Political Science Review, 94(1), 21–36.10.1017/S0003055400220078 Search in Google Scholar

Buhaug, H., Cederman, L.-E. & Gleditsch, K. S. (2014). Square pegs in round holes: inequalities, grievances, and civil war. International Studies Quarterly, 58(2), 418–431.10.1111/isqu.12068 Search in Google Scholar

Cederman, L.-E., Gleditsch, K. S. & Buhaug, H. (2013). Grievances and inequality in civil wars. Cambridge and New York: Cambridge University Press. Search in Google Scholar

Cederman, L.-E., Gleditsch, K. S. & Wucherpfennig, J. (2017). Predicting the decline of ethnic civil war: Was gurr right and for the right reasons? Journal of Peace Research, 54(2), 262–274.10.1177/0022343316684191 Search in Google Scholar

Cirillo, P. & Taleb, N. N. (2016). On the statistical properties and tail risk of violent conflicts. Physica A: Statistical Mechanics and its Applications, 452(15), 29–45.10.1016/j.physa.2016.01.050 Search in Google Scholar

Clauset, A., Young, M. & Gleditsch, K. S. (2007). On the frequency of severe terrorist events. Journal of Conflict Resolution, 51(1), 1–31. Search in Google Scholar

Engene, J. O. (2007). Five decades of terrorism in Europe: The TWEED dataset. Journal of Peace Research, 44(1), 109–121.10.1177/0022343307071497 Search in Google Scholar

Gaddis, J. L. (1992/1993). International relations theory and the end of the cold war. International Security, 17, 5–58.10.2307/2539129 Search in Google Scholar

Gleditsch, K. S. & Clauset, A. (2017). Trends in conflict: What do we know and what can we know?. Wolforth, W. & A. Gheciu (Eds.), Oxford handbook of international security. New York and Oxford: Oxford University Press. Search in Google Scholar

Gleditsch, K. S. & Ward, M. D. (2013). Forecasting is difficult, especially about the future: Using contentious issues to forecast interstate disputes. Journal of Peace Research, 50(1), 17–31.10.1177/0022343312449033 Search in Google Scholar

Gleditsch, K. S. & Polo, S. M. T. (2016). Ethnic inclusion, democracy, and terrorism. Public Choice, 169(3), 207–229.10.1007/s11127-016-0360-5 Search in Google Scholar

Gleditsch, K. S., Polo, S. M. T. & Ruggeri, A. (2017). A transformation of political violence? The decline of conflict and terrorism. Paper presented at the annual meeting of the International Studies Association, Baltimore, MD, 22–25 February. Search in Google Scholar

Global Terrorism Index. (2015). Sydney: Institute for Economics and Peace. Search in Google Scholar

Goldstein, J. S. (2011). Winning the war on war. Hialeah, FI: Dutton/Penguin. Search in Google Scholar

Gurr, T. R. (2000). Ethnic warfare on the wane. Foreign Affairs, 79(3), 52–64.10.2307/20049729 Search in Google Scholar

Hanson, R. (2008). Catastrophe, social collapse, and human extinction. Bostrom, N. & M. Cirkovic (Eds.), Global catastrophic risks (pp. 363–377). Oxford: Oxford University Press. Search in Google Scholar

Hechter, M., Kuran, T., Tilly, C., Collins, R. & Kieser, E. (1995). Symposium on prediction in the social sciences. American Journal of Sociology, 100(6), 1520–1615. Search in Google Scholar

Hegre, H., Metternich, N. W., Nygård, H. M. & Wucherpfennig, J. (2017). Forecasting in peace research. Journal of Peace Research, 54(2), 113–124.10.1177/0022343317691330 Search in Google Scholar

Kuran, T. (1989). Sparks and prairie fires: A theory of unanticipated revolution. Public Choice, 61(1), 41–74.10.1007/BF00116762 Search in Google Scholar

Lohmann, S. (1994). The dynamics of informational cascades: The monday demonstrations in leipzig, East Germany, 1989–91. World Politics, 47(1), 42–101.10.2307/2950679 Search in Google Scholar

Mueller, J. & Stewart, M. G. (2011). Terror, security, and money: Balancing the risks, benefits, and costs of homeland security. Oxford and New York: Oxford University Press. Search in Google Scholar

Mueller, J. & Stewart, M. G. (2015). Chasing ghosts: The policing of terrorism. Oxford and New York: Oxford University Press. Search in Google Scholar

Oneal, J. R. & Russett, B. M. (2001). Triangulating peace: democracy, interdependence, and international organizations. New York: Norton. Search in Google Scholar

Pinker, S. (2011). The better angels of our nature: Why violence has declined. New York: Viking. Search in Google Scholar

Polo, S. M. T. & Gleditsch, K. S. (2016). Twisting arms and sending messages terrorist tactics in civil war. Journal of Peace Research, 53(6), 815–829.10.1177/0022343316667999 Search in Google Scholar

Popper, K. (1959). The logic of scientific discovery. Camberley: Hutchinson. Search in Google Scholar

Ray, J. L. & Russett, B. M. (1996). The future as arbiter of theoretical controversies: Predictions, explanations and the end of the cold war. British Journal of Political Science, 26, 441–470.10.1017/S0007123400007560 Search in Google Scholar

Richardson, L. F. (1948). Variation of the frequency of fatal quarrels with magnitude. Journal of the American Statistical Association, 43(244), 523–546.10.1080/01621459.1948.10483278 Search in Google Scholar

Taleb, N. N. (2007). The black swan: The impact of the highly improbable. New York: Random House. Search in Google Scholar

Ward, M. D. & Gleditsch, K. S. (2002). Location, location, location: An MCMC approach to modeling the spatial context of war and peace. Political Analysis, 10(3), 244–260.10.1093/pan/10.3.244 Search in Google Scholar

Ward, M. D., Metternich, N. W., Dorff, C. L., Gallop, M., Hollenbach, F. M., Schultz, A. & Weschle, S. (2013). Learning from the past and stepping into the future: Toward a new generation of conflict prediction. International Studies Review, 15(4), 473–490.10.1111/misr.12072 Search in Google Scholar

Published Online: 2017-10-20

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