Violence and the Geographic Concentration of Political Power

Jordan Adamson (Clemson University)

Abstract: Is there more political violence in geographic areas with more countries? This question was raised by classical and historical scholars but remains unanswered by the modern literature on violence and the state. To empirically address this question I compile a spatio-temporal data set on Africa between 1990 and 2015. I create a novel measure called ``geo-political concentration'', with a monopoly value at 1, by calculating a Herfindahl–Hirschman Index of country surface areas for a given geographic area. I find a non-linear relationship between armed political violence geo-political concentration in both a bi-variate non-parametric regression and multivariate OLS. As an area becomes geo-politically monopolized the reduction in violence is initially large, but plateaus, and eventually slightly reverses. Furthermore, I find that the type of violence changes as HHI increases and that a more pronounced U-shape is found when looking at larger geo-graphic regions.