The probability P(X≥x) of war fatalities (per war); the black point marker represents the empirical distribution, the green line is the best fit obtained by means of lognormal function and the red line is a best fit of power law cutting the tails of distribution. In the subfigure we show the power law fit of a tail distribution. Graphic: Martelloni, et al., 2019 / Arxiv
The probability P(X≥x) of war fatalities (per war); the black point marker represents the empirical distribution, the green line is the best fit obtained by means of lognormal function and the red line is a best fit of power law cutting the tails of distribution. In the subfigure we show the power law fit of a tail distribution. Graphic: Martelloni, et al., 2019 / Arxiv

4 January 2019 (Emerging Technology) – War is the subject of detailed study among historians, reflecting a general hope that by learning from the past, we can avoid similar mistakes in future.

Many historians study war in terms of the actors involved and the decisions they make. It is often possible to describe how wars emerge from these stresses and to identify patterns of behavior that should be avoided in future.

But in recent years another, more powerful way to think about war has emerged. In this way of thinking, war is a simple but unavoidable network phenomenon that is hard-wired into the structure of society.

The thinking goes like this. Society is a complex web of social, political, and economic forces that depend on the network of links between individuals and the countries they represent. These links are constantly rearranging, sometimes because of violence and death. When the level of rearrangement and associated violence rises above a threshold level, we describe the resulting pattern as war.

This network science approach is providing a new way to think about how to avoid the causes of war. But it raises important questions, too. Not least of these is whether this new approach is evidence-based at all: does the historical record provide good evidence that war is a network phenomenon?

Today, we get an answer thanks to the work of Ugo Bardi at the University of Florence in Italy and a couple of colleagues, who have analyzed one of the largest historical databases of violent conflict and say its statistical properties are entirely consistent with the network theory of war.  “Our result tends to support the idea that war is a statistical phenomenon related to the network structure of the human society,” they say.

Bardi and co begin with a data set compiled by Peter Brecke at Georgia Tech University in Atlanta, which consists of the number of war fatalities each year between 1400 and 2000. […]

This makes the possibility of future major conflict uncomfortably high. As Clauset put it: “The historical patterns of war seem to imply that the long peace may be substantially more fragile than proponents believe.” A sobering conclusion. [Here’s another interesting paper that uses other methods on the same data set to come to a similar conclusion: Is War Disappearing? –Des] [more]

Data mining adds evidence that war is baked into the structure of society


Distribution of war fatalities per war world population normalized fitted by power law (equation 1): a=0.000332, b=-0.8869, SSE=0.0005404, R2=0.9991, Adjusted-R2=0.9991, RMSE=0.002478. Graphic: Martelloni, et al. 2018 / Arxiv
Distribution of war fatalities per war world population normalized fitted by power law (equation 1): a=0.000332, b=-0.8869, SSE=0.0005404, R2=0.9991, Adjusted-R2=0.9991, RMSE=0.002478. Graphic: Martelloni, et al. 2018 / Arxiv

ABSTRACT: We analyze the database prepared by Brecke (Brecke 2011)  for violent conflict, covering some 600 years of human history. After normalizing the data for the global human population, we find that the number of casualties tends to follow a power law over the whole data series for the period considered, with no evidence of periodicity. We also observe that the number of conflicts, again normalized for the human population, show a decreasing trend as a function of time. Our result agree with previous analyses on this subject and tend to support the idea that war is a statistical phenomenon related to the network structure of the human society.CONCLUSIONS: Our contribution in this field consists in validating the Brecke conclict database (Brecke 2011), among the longest and most complete ones available. This analysis confirms previous work, see e.g. (Clauset 2018), (Clauset and Gleditsch 2018) for a general discussion. The data indicate that power laws are common in the distribution of violent conflicts in human history: in this case, the trend is clear when the number of casualties are normalized for the increasing world population. Note also that the normalized number of conflicts per year tend to decrease with time – this result indicates that in modern times wars have tended to become less frequent but more destructive. In practice, these result confirm that there is little evidence supporting the idea popularized by Pinker (Pinker 2011) that humankind is progressing toward a more peaceful world. A new major conflict might be possible in a non-remote future, as discussed among others by Clauset (Clauset 2018). These result seem to indicate that human conflicts are a critical phenomenon: we could say that humans worldwide tend to form societies existing in a self-organized critical condition, as defined by Bak et al. (Per Bak, Tang, and Wiesenfeld 1988). In these conditions, war is simply one of the methods that the system has to dissipate entropy at the fastest possible speed (Kleidon, Malhi, and Cox 2010), (Trinn 2018). In other words, war appears to be an unavoidable consequence of the behavior of human beings, and perhaps of other primate species (de Waal 2000). On the other hand, we need also to remark that the available data series involves only a small fraction of human history, corresponding to a period of tumultuous and rapid expansion of both the economy and the population. A future of declining natural resources might show different trends.

Pattern Analysis of World Conflicts over the past 600 years