The world has become more peaceful

The world has become more peaceful
The world has become more peaceful, points out Håvard Mokleiv Nygård. Credit: Yngve Vogt

Although the war in Syria is in its eighth year, statisticians have established that the world is becoming increasingly peaceful.

For a number of years, the Peace Research Institute Oslo (PRIO) has used statistics to conduct research about armed conflicts. They work closely with some of the country's foremost statisticians at the University of Oslo in Norway.

"We could not have conducted our research without extensive use of statistics," points out Håvard Mokleiv Nygård, research director at PRIO.

Ever since its founding in 1959, the Institute has researched why war happens, how war develops and what steps can be taken to halt conflicts.

To do this, PRIO has systematically collected data from all possible conflicts, the countries that are at war, and how many are killed. The statistics show that fewer people than previously die in war.

"The wars after the Korean War (1950–1953) have killed a quarter as many people as the wars before the Korean War," says Nygård.

He calls such a change, here regarding the number of people killed in battle, viewed over time, a .

"The change after this breaking point is an indication that the world has become a more peaceful place."

Statisticians who work with Håvard Mokleiv Nygård say it is nevertheless statistically uncertain when the breaking point occurred.

"Although the Korean War is the best guess, the breaking point could also have been in 1945 or at the end of the Vietnam War. However, although the exact time is uncertain, we still see a clear difference between the number of killed before and after the breaking point," points out Nils Lid Hjort, professor of statistics at the Department of Mathematics at the University of Oslo.

International disagreement

The postulate that the world has become more peaceful was put on the international agenda in 2011 by Harvard professor Steven Pinker in his book about the history of violence, "The Better Angels of Our Nature." He built a lot of his research on datasets from PRIO.

Not everyone agreed with his conclusion. One of them is Professor Aaron Clauset from the University of Colorado in Boulder. He believes that the data base is not good enough for drawing such a conclusion.

The discussion also revolves around the the being used.

"The distribution of the number of people dying in war does not follow any normally distributed curve. There are many wars in the middle of the curve with a certain number of killed and few wars on the curve's extremes, with few or many killed. Wars can erupt that kill a great many people. An example is the Second World War. A Third World War can also occur, in principle, with 150 million killed," says Håvard Mokleiv Nygård to the research magazine Apollon.

Many of the statistical tools used in social science research work well, provided the statistical distributions involved are like the classical normal or Gaussian, or from a range of not-so-extreme models. The number of persons killed in wars, however, follows more complicated patterns, often of the so-called power-law type. These have long tails, with high enough probabilities for even very large outcomes.

This is why the mathematicians from Blindern got involved. They have launched new methods for finding change points in time series where the data follow such power-law distributions.

"The statistical power-law distributions are challenging, regarding probability theory and statistical inference. Although some phenomena are very rare, such as very high death figures, we have taken this into account in our analyses," says Nils Lid Hjort.

Aaron Clauset also worked with such power-law distributions, but the mathematicians at UiO have developed the mathematics a notch further and have come to a different conclusion.

Their disagreement is not about where the breaking point is, but whether it is possible to say that the world has become more peaceful.

Clauset believes that the trend after the Korean War must continue for another 150 years before he is comfortable, purely statistically speaking, saying that the world has become more peaceful.

The mathematicians at UiO disagree with him.

"We can already now say that the world has become a more peaceful place," says Céline Cunen, postdoctoral fellow at the Department of Mathematics at UiO. The mathematical methods were part of her thesis for which she recently earned her Ph.D.

Impact on war

The mathematicians have also looked at the circumstances that affect the number of deaths in a war. Examples include the level of democracy and scope of trading measured a year before
the war erupted.

"Our idea is: The more trade a country has with other countries, the less risk of war," says Céline Cunen.

Their data are derived from a war database that contains information about all wars dating back to 1800. It shows which countries have been at war with each other and how many were killed. The last recorded war in the database is from 2003. That was when the United States invaded Iraq. In order for a war to be recorded in this particular database, at least two countries must be at war, with at least a thousand killed in one of the countries.

Their analysis does not take civil wars into account, such as the soon eight-year-long civil war in Syria.

There have been fewer and fewer interstate conflicts. There was a gradual increase in civil wars leading up to 1992. The trend turned in 2011 with the Arab Spring. Since then, the number of civil wars has flared up again.

The mathematicians now want to test their new method using data from both interstate and civil wars.

All conflicts

A natural question is whether it would have been possible to predict a big war such as the Second World War.

"The models can also be used to say whether the First or Second World War could have been foreseen, based on the conflict data we had before the wars started. It's very rare for a conflict to start overnight. There are often escalations from something very small, to something very big," says Håvard Mokleiv Nygård.

A more recent example is the Falklands War in 1982, which started with sanctions and bickering and ended in full-out war.

In order to investigate how a conflict can develop into war, PRIO also uses another conflict database. This database contains information about all conflicts since 1946 where more than 25 have been killed over the course of one year.

The researchers are now developing statistical tools that can determine when crises and disputes between countries escalate into wars. In other words, they model the escalation.

"In order to handle conflicts while they are still small, we need to understand how conflicts develop. Once we understand this, we hope that it will become possible to deal with conflicts and stop them in time. Without statistical analysis, it is impossible to do so," Nygård points out.

"The world spends far too few resources today on prevention. Steps are not taken until after the fact. We still know too little about how to prevent conflicts. It is then important to understand the breaking points in order to prevent conflicts in a systematic and manageable manner."

The research project can theoretically be used to study what could have been done to prevent past conflicts.

"We have already been able to determine that a number of conflicts could have been considerably smaller if peacekeeping forces had been deployed. It is not ethically defensible to initiate an experiment where some countries receive peacekeeping forces and others do not. We must therefore use statistical tools that can simulate the experiment," explains Håvard Mokleiv Nygård.

Over the next three years, Gudmund Horn Hermansen, associate professor at the Department of Mathematics, intends to find the reasons why conflicts escalate.

He will look at the interaction between non-violent and violent protests and what it means for a conflict to escalate and why some conflicts stop.

"Our ambition is to be able to say what it takes to escalate a and how it is possible to prevent this from happening," says Gudmund Horn Hermansen.

Explore further

A statistical look at the probability of future major wars

Provided by University of Oslo
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User comments

Feb 15, 2019
So Afghanistan is a "civil war"?

Feb 15, 2019
I was expecting a graph of the number of violent deaths for every million people. Is that too much to ask? That graph would save many words in this paper, and time is something that we do not want to waste.

Lots of words usually are hidding something, especially in delicate matters like this topic.

Sorry if it is found to be rude from my part.

Feb 15, 2019
So why is the world so close to nuclear armageddon?

This is just another case of statistical manipulation..

Feb 15, 2019
The true breaking point came in 1973 with roe v wade and the subsequent ABORTION of over ONE BILLION unborn people worldwide. Worldwide family planning efforts prevented perhaps a billion more births.

Perhaps one quarter of the worlds population and their descendants to the 2nd and 3rd generation, never born. THIS is what has reduced the frequency and intensity of war.

War and revolution have been limited to those cultures still in the throes of ancient religions expressly designed to outgrow and overwhelm each other. In the west, these religionist cultures were eradicated by the world wars. The subsequent reductions in growth and the resulting peace and prosperity that followed could not have occurred without the destruction of these cultures, which leads one to conclude that this was the main reason these wars were waged.

Feb 15, 2019
why is the world so close to nuclear armageddon?
Its not. It probably would already have succumbed if the world wars hadnt created the tripartite superpowers and put overwhelming control of these weapons, and the means to deliver them, in their hands.

The cold war was a sham staged to facilitate this.

The one clear fact that puts this all into perspective, is that any one of these nuclear-armed states could have smuggled nukes into major cities and capitals, planted them in undetectable locations impossible to find, and blackmailed each other into submission.

This would have been an inevitability in the prewar structure of world politics, making war unavoidable.

So, given the FACT that nuclear weapons were an inevitable development, what we see is the most stable way of ensuring that war would NOT happen.

Such an unlikely and complex result could not have been the product of happenstance. It was anticipated, planned for, and constructed. The historical norm.

Feb 15, 2019
Lack of wars and deaths in (inter country) wars does not make a peaceful world.
Political executions, ethnic cleansings, genocides, civil wars, suicide bombings,
(non death) beatings - shootings - and stabbings, and just basicly living in fear
are happening All over the world and to great extent.
"More peaceful world" my ass!

Feb 15, 2019
Lack of wars and deaths in (inter country) wars does not make a peaceful world.
Political executions, ethnic cleansings, genocides, civil wars, suicide bombings,
(non death) beatings - shootings - and stabbings, and just basicly living in fear
are happening All over the world and to great extent.
"More peaceful world" my ass!
All driven primarily by overpopulation.

Feb 15, 2019
Why does war follow a power-law distribution?

Because society moves forward in time with a feedback loop process where the future is heavily influenced by the past. Generally, a lot of negative feedback is suppressed leaving us with a positive feedback loop, and positive feedback loops always crash. In this crash means major war.

We know that forests also follow a feedback loop process with power-law crashes (fires). If there were no fires for a long time would that mean the forest is safer? No, it would actually mean the opposite.

The world appears to be getting safer but in reality it is getting much more dangerous. I'm seeing many more articles about the possibility of nuclear war than I used to.

Feb 16, 2019
There is a normative distribution: lies, damn lies, and statistics.

Feb 16, 2019
If there were no fires for a long time would that mean the forest is safer? No, it would actually mean the opposite
Forests can be said to follow economic cycles just like human populations. The 4 phases: growth, decay, collapse, rebirth. In humans this cycle is driven by overgrowth. In forests it is driven by the need to clean out the deadwood and the underbrush.

Economic cycles can be used to the same effect among humans.
The world appears to be getting safer but in reality it is getting much more dangerous. I'm seeing many more articles about the possibility of nuclear war than I used to
-Yeah, wars and rumors of wars blahblah. You need to be able to discern the difference between politics and news.

Of course like I've been saying, modern wars are planned, staged, and choreographed to produce the most beneficial result.

Might just be Time for spring cleaning. There is tech on the horizon just as dangerous as fissiles. The world must be prepared once again...

Feb 17, 2019
I agree with the poster who asked for a graph. Nevertheless good information. So free trade and many more weapons of war have led to greater peace. A plot of military budgets on weapon systems for the last 150 years vs combat deaths might be interesting.

Feb 17, 2019
Not surprising at all in the modern world which has made war much more expensive than ever before. If you have the military power and are contemplating starting a war, then self-interest suggests you should consider a cost-benefit analysis before attacking. Media coverage has raised the political cost. Participation in global trade has raised the financial cost. The increased cost and destructive power of modern weapons has further raised the financial cost and created uncertainty about outcome. In short, war is often just too expensive and risky in many cases.

I think there are deeper lessons to be learned here, but hey, what do I know?

Feb 17, 2019
There are times, as humans, that we find that facts and reality do not dovetail with the delusions we have invested in. Recognizing that our ability to extrapolate the past and present into possible futures is based on delusional processes, the more perceptive of us came up with scientific methodology.

The problem most of us have with the scientific method is that it is counter-intuitive, and we consequently have a strong tendency to distrust the results, when those results do not align with our previously bought and paid for delusional landscape.

When this happens, as it does so much of the time, the least perceptive among us attack those results based on our personal set of delusions, rather than using a scientific basis for that attack.

Anyone who wishes to be relevant on a forum like this must recognize that as humans, we have a delusional basis, and that a constant vigilance must be maintained against our natural tendency to favor delusion over reality.

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