Verified by 
This week’s headlines include a story of a 9-year-old girl who accidentally shot a man with an Uzi. The event transpired on Monday in my home state of Arizona, at a place called “Bullets and Burgers.” According to their Facebook page:
“Bullets and Burgers is a must try Las Vegas Experience….We separate ourselves from all other Las Vegas ranges with our unique 'Desert Storm' atmosphere and military style bunkers…. Our guests have the opportunity to fire a wide range of fully automatic machine guns and specialty weapons…. Our 50 Cal. selections includes the Barret Sniper Rifle, the Browning BMG .50 Cal('the deuce'), and the Desert Eagle….We even have the actual firearms used in several Hollywood hits including The Terminator and Rambo II.”
Despite the fact that Bullets and Burgers is actually a popular tourist destination for visitors to Las Vegas (Nevada), and that the young girl wielding the Uzi was reportedly a visitor from New Jersey, the press is connecting the event with Arizona’s gun culture, as they did on an earlier occasion when a disturbed young man shot U.S. Representative Gabrielle Giffords and 18 other people in a supermarket parking lot (see Should Arizona claim the insanity defense?). Regarding this week’s event, an Associated Press release says: “Arizona has long had a strong pro-gun culture, including weapon ranges that promote events for children and families.”
Gun cultures
Although I have lived in Arizona for decades, I don’t personally experience much of a gun culture here. By contrast, I did see plenty of gun culture growing up in New York, where many of my friends, neighbors, and relatives owned guns, and several belonged to the National Rifle Association and the local “Rod and Gun Club.” I myself enjoyed the rare opportunities to shoot guns at cans in the woods near my uncle’s house in the country, and was delighted when I was judged old enough to go on a hunting trip. Out here in the Wild Westerm Arizona Territory, by contrast, I hardly know anyone who owns a gun, or at least who discusses it in public. But I live in a university community, so I am likely exposed to a nonrepresentative sample. College professors tend to be Liberals, a group low in gun ownership (a 2013 Gallup poll reports that Conservative Republicans are fully 2½ times more likely to own guns than Liberal Democrats). And on the weekends, I hang out in coffee houses and bookstores, not places where you find many people packing firearms.
Hence, I may be falling prey to what cognitive psychologists call the availability heuristic, which involves basing a judgment on what comes to your mind easily. It often works (as in judging whether there are more McDonalds or Burger Kings in your city), but relying on what comes easily to mind can throw you off if you don’t have an unbiased sample of experiences. I recall an interesting conversation with a student in one of my studies who argued that 50 percent of the men at ASU were gay. Actual surveys of the undergraduate population show numbers that are well below that, under 5 percent. But the gay student was no doubt basing his judgment on the folks he encountered in his daily life. And my experiences in a university community are also likely to throw off my judgment of the gun culture in Arizona as a whole.
So what is the actual data?
Going online last night, I discovered that Guns and Ammo magazine ranks Arizona #1 in its list of “Best States for Gunowners.” To score well on this list, a state should have fewer regulations on carrying guns (either concealed or in public), fewer constraints on buying machine guns or silencers, and no restrictions on the number of bullets you can store in your gun’s magazine. Despite my childhood experiences, New York scores at the opposite end of the list – way down at number #50. In the empire state, you need a license for a handgun, you can’t carry loaded guns in your vehicle, you can’t have more than 10 rounds of ammunition in your magazine, and machine guns and silencers are illegal.
Although Guns and Ammo magazine loves Arizona, not all Arizonans love guns and ammunition. Back around the time of the Gabrielle Giffords shooting (see Should Arizona claim the insanity defense?). I discovered that Arizona was actually in the middle of the distribution in terms of percent of the populace who own guns (at 31 percent, compared to over 50 percent in Alabama, Alaska, and Arkansas, and lower than the national average of 37 percent).
Is gun culture linked to homicide rates?
New York (the low scoring state in Guns and Ammo’s rankings) had an average homicide rate of 4.45 (averaged over the years 2000 through 2012), whereas Arizona (the best state according to Guns and Ammo) had a rate of 6.65 over that same period. But those are only two data points. The state with the highest homicide rate was Louisiana (11.98) and its Guns and Ammo ranking of gun friendliness was right in the middle of the pack, at 27th. The lowest homicide rates were found in Iowa (1.55), which ranked lower in gun friendliness than Louisana (at 37th), but still way above New York.
Rather than just selecting random pairs of states, I ran a quick little analysis of the state-by-state homicide rates from 2000 through 2012. I correlated that with gun ownership in each state, as well as the Guns and Ammo gun-friendliness rankings. I also threw in the suicide rates, because those also commonly involve guns, and are much more common than homicides. Suicide rates are typically 2 or 3 times higher than homicide rates, which often surprises us (that availability heuristic at work again. Robin Williams notwithstanding, the media does not typically pay as much attention to suicides, so we don’t hear as much about them, and most of us obsess less over other people’s suicides than the chance of some random stranger shooting us in a drive-by)
Fig. 1: Gun Friendliness and Homicide Rates
What my quick analyses revealed was surprising in some ways, but not in others. The Guns and Ammo rankings were highly correlated with gun ownership by state (-.66). That is unsurprising because Guns and Ammo included gun ownership as one of the determinants in its rankings (it could have been much lower, though, since their primary criteria involved the state’s laws restricting arms ownership and use). There was also a correlation between the Guns and Ammo rankings and the state’s homicide rates, but it was weaker (-.16, meaning if Guns and Ammo ranked a state as more gun friendly, homicide rates were higher, see Figure 1).
Fig. 2: Homicide rate and gun ownership rates
It was surprising, however, that the correlation between actual gun ownership and homicide rates was nonexistent (.00 in my quick analysis, see Figure 2).
If you want to worry about being killed, other data suggests that you should instead worry about your state or province’s income inequality, which is a strong predictor of homicide rates (Daly, Wilson, & Vasdev, 2001). Nevertheless, before you jump to the conclusion that you’d be neither more nor less safe if you personally bought a gun, you should consider the suicide statistics. It turns out that there is a rather strong correlation between suicides and a state’s gun friendliness (-.52) and more importantly, between suicides and gun ownership (.49), as depicted in Figure 3 (about half of all suicides are committed with guns). And it’s not just yourself you have to worry about. According to one study, suicide rates among gun owner’s adolescent children are four times higher than in homes without firearms, and are especially pronounced in homes where the guns are kept unlocked and loaded (Miller & Hemenway, 2008).
Fig. 3: Suicide by gun ownership rates
The Arizona Uzi incident was of course not a homicide, but an accident. Accidental homicides by firearm discharges are much less likely than are intentional gun homicides. According to the CDC, for example, there were 11,101 homicides by firearms, compared to 851 by accidental discharge of firearms in the U.S. in 2011. According to the National Shooting Sports Foundation, the death rate by accidental discharge of guns has, like that for homicides, been dropping over the last two decades, but the odds of getting accidentally killed by a gun in 2010 (the year for which they report) were substantially higher in Arizona (.19) than in New York (.07). Louisiana, which also tends to have the highest homicide rates, also had the highest rate of accidental deaths by gunshot (.95 in 2010).
Where is your state?
In the course of searching around for statistics on homicides, I found some interesting graphic depictions. One of them (figure 4) shows the rate of homicide by state, as well as comparison rates North and South of the Border.
Fig. 4 Homicide rates in U.S. and neighboring countries
Another interesting graph compares rates in different U.S. cities to other places in the world. The U.S. homicide rate is several times higher than that of comparable first-world countries, such as Britain and Australia, but there are much bloodier places one could live, such as Venezuela, Columbia, and Honduras. Nevertheless, another interesting graph illustrates that particular U.S. cities are more like Third-World countries in their homicide rates (figure 5). Living in Phoenix is comparable to living in Mexico, whereas living in New York is comparable to the more pacific Argentina. On that map, Louisiana again looks especially dangerous, with New Orleans comparable to the very bloody Honduras.
Fig. 5: Murder rates in U.S. cities compared to other countries
Fig. 5: Murder rates in U.S. cities compared to other countries
Scientific evidence and the biased mind
How does one’s mind handle complicated statistics like these, and news events like the death of an instructor showing a girl how to fire an automatic weapon? If you go online, you will see that gun advocates and gun-control advocates can look at the same event, or the same statistics, and come to opposite conclusions. There is a fascinating study by Charlie Lord and his colleagues (1979), who demonstrated that the tendency to bias our interpretation of evidence is found even among Stanford students (who are highly selected for their logical abilities). Presented with the exact same scientific evidence, Stanford students who favored the death penalty came away convinced they were right, whereas those who opposed the death penalty came to opposite conclusions, based on the same evidence. More generally, our personal experiences, and our opinions, don’t always match up perfectly with the data. It’s tough to be open-minded in looking at statistical data. Of course, not all information processing is biased, and some people, some of the time, can overcome their biases. In a later study, Lord and his colleagues (1984) found that it helps to play your own “devil’s advocate” – that is, to ask yourself what you would conclude if the evidence fell in the opposite direction.
Related blogs
On dodging bullets, and stereotypes, out in the Wild West.
References
CDC: http://www.cdc.gov/nchs/data/nvsr/nvsr61/nvsr61_06.pdf
Daly, M., Wilson, M., & Vasdev, S. (2001). Income inequality and homicide rates in Canada and the United States. Canadian J. Criminology, 43, 219-236.
Gallup poll (http://www.gallup.com/poll/160223/men-married-southerners-likely-gun-owners.aspx)
Lord, C. G., Lepper, M. R., & Preston, E. (1984). Considering the opposite: A corrective strategy for social judgment. Journal of Personality and Social Psychology, 47, 1231–1243.
Lord, C. G., Ross, L., & Lepper, M. R. (1979). Biased assimilation and attitude polarization. Journal of Personality and Social Psychology, 37, 2098–2109.
Miller, M., & Hemenway, D. (2008). Guns and suicide in the United States. New England Journal of Medicine, 359, 989–991.
