Ward's research was supported by grants from the Methods, Measurement, and Statistics Program at the National Science Foundation, numbers SES-0417559 and SES-0631531. This research greatly benefitted from many helpful suggestions from Kristin M. Bakke, Nathaniel Beck, Bear F. Braumoeller, Bruce Bueno de Mesquita, John R. Freeman, Jeff Gill, Kristian Skrede Gleditsch, Peter D. Hoff, Gary King, Aseem Prakash, Adrian Raftery, Dennis L. Ward, Anton Westveld, and Erik Wibbels. David Callaway and John E. Daniels of the Social Science Data Service at the Institute of Governmental Affairs at the University of California, Davis were especially helpful to us at a critical point in our quest for distributed computing resources, which we found at the San Diego Supercomputer Center at the University of California, San Diego. We thank Chris Adolph for sharing his code for “ropeladder” plots (http://faculty.washington.edu/cadolph/code.shtml). Finally, we thank reviewers for helpful and invigorating comments.
Disputes, Democracies, and Dependencies: A Reexamination of the Kantian Peace
Version of Record online: 19 JUN 2007
American Journal of Political Science
Volume 51, Issue 3, pages 583–601, July 2007
How to Cite
Ward, M. D., Siverson, R. M. and Cao, X. (2007), Disputes, Democracies, and Dependencies: A Reexamination of the Kantian Peace. American Journal of Political Science, 51: 583–601. doi: 10.1111/j.1540-5907.2007.00269.x
Summaries of the literature on the democratic peace include Chan (1997), Ray (1998), and Morrow (2002). An incomplete list of articles on this topic would include , , Lake (1992), Maoz and Russett (1993), Farber and Gowa (1995), Ray (1995), Maoz (1996), Rousseau et al. (1996), Farber and Gowa (1997), Gleditsch and Hegre (1997), Mansfield and Snyder (1997), Mousseau (1997), Oneal and Russett (1997), Raknerud and Hegre (1997), Thompson and Tucker (1997), Gartzke (1998), Maoz (1998), Russett, Oneal, and Davis (1998), Cederman (2001), Russett and Oneal (2001), Schultz (2001), Huth and Allee (2002), Dixon and Senese (2002), Russett, Oneal, and Berbaum (2003), and Goertz, Jones, and Diehl (2005), among many others.
- Issue online: 19 JUN 2007
- Version of Record online: 19 JUN 2007
Militarized interstate disputes are widely thought to be less likely among democratic countries that have high levels of trade and extensive participation in international organizations. We reexamine this broad finding of the Kantian peace literature in the context of a model that incorporates the high degree of dependency among countries. Based on in-sample statistical tests, as well as out-of-sample, predictive cross-validation, we find that results frequently cited in the literature are plagued by overfitting and cannot be characterized as identifying the underlying structure through which international conflict is influenced by democracy, trade, and international governmental organizations. We conclude that much of the statistical association typically reported in this literature apparently stems from three components: (1) geographical proximity, (2) dependence among militarized interstate disputes with the same initiator or target, and (3) the higher-order dependencies in these dyadic data. Once these are incorporated, covariates associated with the Kantian peace tripod lose most of their statistical power. We do find that higher levels of joint democracy are associated with lower probabilities of militarized interstate dispute involvement. We find that despite high statistical significance and putative substantive importance, none of the variables representing the Kantian tripod is associated with any substantial degree of predictive power.