- "Figure 3 compares the Poisson distribution with Richardson's data for a group of [outbreaks of] magnitude- 4 wars. The match is very close. Richardson performed a similar analysis of the dates on which wars endedâ€â€the "outbreaks of peace"â€â€with the same result. He checked the wars on Quincy Wright's list in the same way and again found good agreement. Thus the data offer no reason to believe that wars are anything other than randomly distributed accidents."
- "Richardson also examined his data set for evidence of long-term trends in the incidence of war. Although certain patterns catch the eye when the data are plotted chronologically, Richardson concluded that the trends are not clear enough to rule out random fluctuations. "The collection as a whole does not indicate any trend towards more, nor towards fewer, fatal quarrels." He did find some slight hint of "contagion": The presence of an ongoing war may to some extent increase the probability of a new war starting."
- "Of 94 international wars with just two participants, Richardson found only 12 cases in which the two combatants had no shared boundary, suggesting that war is mostly a neighborhood affair."
- "What about other causative factorsâ€â€social, economic, cultural? While compiling his war list, Richardson noted the various items that historians mentioned as possible irritants or pacifying influences, and then he looked for correlations between these factors and belligerence. The results were almost uniformly disappointing. Richardson's own suppositions about the importance of arms races were not confirmed; he found evidence of a preparatory arms race in only 13 out of 315 cases. Richardson was also a proponent of Esperanto, but his hope that a common language would reduce the chance of conflict failed to find support in the data. Economic indicators were equally unhelpful: The statistics ratify neither the idea that war is mainly a struggle between the rich and the poor nor the view that commerce between nations creates bonds that prevent war. The one social factor that does have some detectable correlation with war is religion. In the Richardson data set, nations that differ in religion are more likely to fight than those that share the same religion."
- "The residuum of all these noncauses of war is mere randomnessâ€â€the notion that warring nations bang against one another with no more plan or principle than molecules in an overheated gas. In this respect, Richardson's data suggest that wars are like hurricanes or earthquakes: We can't know in advance when or where a specific event will strike, but we do know how many to expect in the long run. We can compute the number of victims; we just can't say who they'll be."
From Scale Invariance in Global Terrorism by A. Clauset and M. Young:
In exploring the distribution of the severity of events in global terrorism, we have found a surprising and robust feature: scale invariance. Traditional analyses of terrorism have typically viewed catastrophic events such as the 1995 truck bombing of the American embassy in Nairobi, Kenya, which killed or injured more than 5 200, as outliers. However, the property of scale invariance suggests that these are instead a part of a statistically significant global pattern in terrorism. Further, we find little reason to believe that the appearance of power laws in the distribution of the severity of an event is the result of either reporting bias or changes in database management. This suggests that the power law distribution, with alpha = 2, is an inherent feature of terrorism and counter-terrorism. Indeed, the severity distribution itself has changed very little over the past 37 years of recorded events (Fig. 2), in spite of a dramatic increase in the frequency of events. This small growth in the breadth of the severity distribution may be the result of technological changes, such as the power and availability of cheap explosives and firearms.
Surprisingly, the scale-invariance result extends beyond the total collection of events. When we examine the distributions for major industrialized nations versus the rest of the world, we find that heavy tails are present in both (Fig. 1c), but with substantially different exponents: G7 = 1.71 ± 0.03 versus nonG7 = 2.5 ± 0.1. That is, while events occur much less frequently in major industrialized nations, when they do, they are much more severe (on average) than events outside those nations. Additionally, when events are partitioned by weapon type, statistically significant power laws persist (Fig. 3, Table II) and show that any roughness in the scaling of the aggregate distributions (e.g., Fig. 1a) is derived from the composition weapon-specific power laws with distinct scaling parameters and ranges. It also illustrates that there is something unique about explosives, which causes the shallow scaling of the lower tail for the injuries severity distribution.
From From old wars to new wars and global terrorism by Johnson, Spagat and some other fellows:
Even before 9/11 there were claims that the nature of war had changed fundamentally. The 9/11 attacks created an urgent need to understand contemporary wars and their relationship to older conventional and terrorist wars, both of which exhibit remarkable regularities. The frequency-intensity distribution of fatalities in "old wars", 1816-1980, is a power-law with exponent 1.80. Global terrorist attacks, 1968-present, also follow a power-law with exponent 1.71 for G7 countries and 2.5 for non-G7 countries. Here we analyze two ongoing, high-profile wars on opposite sides of the globe - Colombia and Iraq. Our analysis uses our own unique dataset for killings and injuries in Colombia, plus publicly available data for civilians killed in Iraq. We show strong evidence for power-law behavior within each war. Despite substantial differences in contexts and data coverage, the power-law coefficients for both wars are tending toward 2.5, which is a value characteristic of non-G7 terrorism as opposed to old wars. We propose a plausible yet analytically-solvable model of modern insurgent warfare, which can explain these observations.
Power laws, yet again making the world a more interesting place and making ideologies right and left look silly, silly, silly.
