Guns and Homicide: Worldwide Statistics

Posted on December 16, 2012 by

45


corr-gunvhomo

Just the numbers.

keywords: Guns, Violence, Correlation

In light of the recent news and discussion of guns and gun control I spent some time analyzing the data regarding gun ownership and homicide world wide in more than 170 countries.  I report various statistics regarding the relationship between gun ownership rates, homicide rates, and homicide due to gun rates.

The Data

These charts are based on data from two sources:

I combined these two datasets in order to assess the relationship between gun ownership and overall homicide rates.  There is a lot of missing data, so for some plots not all countries are represented.

If you are interested to crunch the numbers yourself, the data is here: gun-stats-raw

Chart 1: Gun ownership versus homicide rate: scatter & correlation

In this chart each data point represents one country.  The X location is determined by the gun ownership rate of the country. The Y location is determined by the homicide rate per 100,000 people. The US leads the world in guns per 100 people at 88.8.  The US is the dot at the furthest right.

The red trend line was determined using linear regression.  The correlation is -0.17. This indicates that higher gun ownership rates are correlated with lower homicide rates.  However this value is not an especially strong correlation.

corr-gunvhomo

X = gun ownership / 100 people. Y = homicide rate / 100,000.

Chart 2: Gun ownership versus homicide by gun rate: scatter & correlation

In this chart each data point represents one country.  The X location is determined by the gun ownership rate of the country. The Y location is determined by the percentage of all homicides caused by guns. The US leads the world in guns per 100 people at 88.8.  The US is the dot at the furthest right.

The red trend line was determined using linear regression.  The correlation is 0.10. This indicates that higher gun ownership rates are correlated with a higher proportion of homicides by gun.  However this value is not an especially strong correlation.

X = gun ownership / 100 people. Y = % of homicides by gun.

X = gun ownership / 100 people. Y = % of homicides by gun.

Chart 3: Gun ownership versus homicide rate: Separate plots

In this chart the countries are sorted left to right by gun ownership rates (further right means more guns per 100 people). The US leads the world in guns per 100 people at 88.8.  The US is at the furthest right.

The red line indicates guns / 100 people. The blue line indicates homicides per 100,000 people. If increased gun ownership were correlated with increased homicide rates we should see the blue line increase as we go right. We do not see that.

chart1-firearms-homicide

X = world wide rank in terms of gun ownership rate (more guns to the right). Y for red line = number of guns/100 people. Y for blue line = homicides/100,000 people.

Chart 4: Homicide rate versus gun ownership: Separate plots

In this chart the countries are sorted left to right by homicide rates (further right means more homicides per 100,000 people).

The red line indicates guns / 100 people. The blue line indicates homicides per 100,000 people.  The US is the big spike in the red line in the middle. The US is about in the middle with regard to overall homicide rates.

If increased gun ownership were correlated with increased homicide rates we should see the red line increase as we go right. We do not see that. In fact it seems to decrease somewhat as we move to the right.

chart2-homicide-firearm

X = world wide ranking according to homicide rate (more homicides to the right). Y for red line = number of guns/100 people, Y for blue line = homicides/100,000 people.

Chart 5: Gun ownership versus homicides due to guns: Separate plots

In this chart the countries are sorted left to right by gun ownership rates (further right means more guns per 100 people).

The red line indicates guns / 100 people. The blue line indicates the % of homicides due to guns.  The US is the furthest right.

If increased gun ownership rates were correlated with increased homicides due to guns we should see the blue line increase as we go right. We do not see that. Overall, the relationship seems random. Perhaps there is some correlation at the very right side. Maybe these are the developed countries?  We’ll check that out in the next chart.

chart3-firearm-homicidepercent

X = world wide ranking according to gun ownership rate. Y for red line = guns/100 people, Y for blue line = % of homicides that were caused by guns.

Chart 6: Gun ownership versus homicide rates in developed countries

In this chart we focus on 45 developed countries (list of developed countries at end of post). The countries are sorted left to right by gun ownership rates (further right means more guns per 100 people).

The red line indicates guns / 100 people. The blue line indicates the homicides per 100,000.  The US is the furthest right.

If increased gun ownership rates were correlated with increased homicides we should see the blue line increase as we go right. We do not see that.

chart5-developed-firearm-homiciderate

X = rank among developed nations according to gun ownership rating (more guns to the right). Y for red line = guns/100 people. Y for blue line = homicides/100,000 people.

Commentary

Based on these data, I conclude:

  • Increased gun ownership rates are slightly negatively correlated with homicide rates worldwide. This means that more guns is correlated with fewer homicides.
  • Gun ownership rates are slightly positively correlated with the rate of homicides due to guns. This means that of all the homicides in a country, a higher proportion of them are gun related when there are more guns per person.
  • Increased gun ownership rates are not correlated with homicide rates in developed nations.

There are other studies, including these by Harvard that seem to be somewhat in conflict with the data I charted above. I think, actually, that it is possible for my results, and Harvard’s to be correct. Here’s why: Access to guns is probably a factor in overall homicide rates. However, social factors like poverty and culture play a much more significant role. In a worldwide study these factors overwhelm the data, so the gun ownership/homicide relationship is not apparent (even seems random or unrelated). If you can control for poverty and culture (e.g., a US only study) I believe you may find correlations. I think this is why the Harvard studies show some relationship.

Also, this paper asserts that the measures of gun ownership used by some of the Harvard authors is not accurate.

Developed Countries

 Singapore
 Japan
 Romania
 Lithuania
 South Korea
 Poland
 Austria
 Netherlands
 India
 Taiwan
 Hungary
 United Kingdom
 Bulgaria
 Ukraine
 Belarus
 Israel
 Slovakia
 Portugal
 Ireland
 Albania
 Estonia
 Spain
 Italy
 Denmark
 Argentina
 Turkey
 South Africa
 Luxembourg
 Czech Republic
 Belgium
 Latvia
 Qatar
 Greece
 New Zealand
 Macedonia
 Iceland
 Germany
 Australia
 Canada
 France
 Norway
 Sweden
 Finland
 Switzerland
 United States
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Posted in: public policy