War size distribution: Empirical regularities behind conflicts

This paper analyses the statistical distribution of war sizes. Using the method recently proposed by Clauset, Shalizi, and Newman (2009), we find moderate support for a Pareto-type distribution (power law), using data from different sources (COW and UCDP) and periods. A power law is a plausible model for the size distribution of a pool of all wars and a sample of wars in many years, although the log-normal distribution is a plausible alternative model that we cannot reject. The random growth of conflicts could generate both types of distribution. We study the growth rates of battle deaths and random growth cannot be rejected for most of the distribution, although the results also reveal a clear decreasing pattern; the growth of deaths declines faster if the number of initial deaths is greater