The Dynamics of Warfare: 1816-1965

Stochastic models are constructed to illuminate the dynamic incidence of international warfare during the period from 1816 to 1965. It is argued that the probabilistic structure of this incidence is revealed most clearly through an analysis based on dyads of nations, thereby disassembling multilateral wars such as World War II. The conceptual focus is on a clear delineation of heterogeneity, both over time and over actors, and of contagion, differentiating its addictive and infectious varieties. Departures from randomness are considered as modifications of the Poisson process, and empirical tests of the assumptions are made by analysis of this process. A conclusion of positive infection is supported by the data. An autoregressive model of order 4 is found to fit the interarrival times adequately and account for the infectious behavior. This suggests an infectious impact of moderate time duration.