The Decline of Violent Conflicts: What Do The Data Really Say?

We propose a methodology to look at violence in particular, and other aspects of
quantitative historiography in general, in a way compatible with statistical inference, which needs to accommodate the fat-tailedness of the data and the unreliability of the reports of conflicts. We investigate the theses of “long peace” and drop in violence and find that these are statistically invalid and resulting from flawed and naive methodologies, incompatible with fat tails and non-robust to minor changes in data formatting and methodologies. There is no statistical basis to claim that “times are different” owing to the long inter-arrival times between conflicts; there is no basis to discuss any “trend”, and no scientific basis for narratives about change in risk. We describe naive empiricism under fat tails. We also establish that violence has a “true mean” that is underestimated in the track record. This is a historiographical adaptation of the results in Cirillo and Taleb (2016).