Some Correlations on Mass Shootings, Updated

Estimating through beginning of July, regressions of mass shooting casualties, and mass shooting events:

Figure 1: Mass shooting casualties (killed+wounded), left scale (brown), and mass shooting events (blue bar, right scale). Gray shading denotes assault weapons ban. Orange shading denotes Trump administration. Source: Mother Jones database.

We can analyze correlations using regression analysis (negative binomial for casualties, Poisson for events).

casualtiest = –1.72 – 0.72 bant + 1.21 trumpt + 0.32 bident +0.00001popt

Adj-R2 = 0.022, SER = 32.7, NOBS = 391. Bold denotes significance at 10% msl, standard errors corrected for overdispersion (GLM option in EViews).

For number of mass shooting events, count regression (Poisson):

eventst = –5.35 – 0.55 bant + 0.55 trumpt + 0.392 bident +0.00001popt

Adj-R2 = 0.106, SER = 0.678, NOBS = 391. Bold denotes significance at 10% msl, standard errors corrected for overdispersion (GLM option in EViews).

Population for June and July extrapolated using previous year’s worth of population data (in log first differences).



34 thoughts on “Some Correlations on Mass Shootings, Updated

  1. Steven Kopits

    That’s as awkward a left axis as I have ever seen. Why not just use causalities in absolute numbers and truncate MGM Grand event with a note?

    If you’re somehow trying to convey that the average person is at risk from a mass shooting, well, they’re not. If you’re trying to convey that casualties are up, then the plain vanilla absolute number should show that.

        1. Steven Kopits

          It might have been an improvement. Why would you present the data that way? What are you trying to convey to your audience?

          1. Menzie Chinn Post author

            Steven Kopits: I was trying to convey the fact that the increase in number of mass shooting casualties was not driven by population increase. The US population had increased by 34% between January 1990 and May 2022.

    1. 2slugbaits

      Steven Kopits Why not just use causalities in absolute numbers and truncate MGM Grand event with a note?

      Because Poisson regressions are part of a family of what are known as count models. Count models are used to predict the likelihood of an event, so the number of casualties in any single event isn’t relevant for purposes of those kinds of models. Not sure if you studied count models in econometrics classes,but William Greene’s econometrics textbook is pretty good on count models with some nice examples.

      1. Barkley Rosser

        Of all people, this was one of the rare times that the usually awful Econned was on the money, noting in another thread the relevance of Poisson distributions for studying these sorts of phenomena. Must give credit when due.

        1. Econned

          Let’s talk about “the usually awful”..: here we have “Barkley Rosser” making unprovoked and uncalled for comments about other guests. Must call out “the usually awful” when being their “usually awful” selves.

          1. Barkley Rosser


            I actually say something nice about you, but you have to whine because it is not an unalloyed compliment. Sorry, but you do not deserve unalloyed compliments.

          2. Econned

            “Barkley Rosser”,
            You have to whine because I comment that you are “usually awful”. Sorry, but you do not deserve compliments.

          3. Barkley Rosser


            Oh, this is hilarious, you showing yourself yet again as the rival with CoRev for worthless stupid goal post moving. You get yourself going just trying to string people along in some really stupid pile of garbage.

            Everybody here can see what you are doing and what you are, totally worthless. For once you actually make a semi-informed comment, and I note that you have done so, while reminding people of your absolutely and totally established record as one of the absolutely worst people ever to post here, you have to whine, just confirming exactly what you are.

            Have fun, garbage.

          4. Barkley Rosser


            Just in case you want to attempt to defend your nauseating self here, how about you tell us any post you have ever provided here that provided an intellectual or factual advance. Your comment on Poisson distributions was one of the rare occurrences. Otherwise, you have mostly indulged in inappropriate slams on Menzie, and others, then followed by notorious long goal post moving strings that have been just astoundingly awful all the way.

          5. Econned

            “Barkley Rosser”,
            Your revealed preference (of mentioing my name in a post I haven’t commented on) runs counter your assertion that I am “totally worthless”. Why are you so enamored with someone who is “totally worthless”? Let us know and please find some reason to mention Vernon Smith while you’re at it.

          6. Barkley Rosser


            Oh, there you go, lying again. I did not say you were “totally worthless,” although maybe you suspect you might be. I said you are “usually awful,” but most of my comment in fact complimented you on the relevance of this remark. But you cannot take that and have to start running around moving goal posts like you do so often with alll sorts of false claims. Oh you poor pathetic thing.

          7. Econned

            “Barkley Rosser”,
            I merely quoted your own words from this very thread on July 7, 2022 at 9:08 pm. Why don’t you elucidate how your comment that “Everybody here can see what you are doing and what you are, totally worthless”, is not you suggesting that I am “totally worthless”. You literally said that’s what I am. If you’re having difficulties, feel free to phone your physician, or even your friend Vernon, because you’re in serious need of a lifeline (yet again). Unable to remember your own comments… so exactly who is the “poor pathetic thing”?

  2. Macroduck

    Prior to the assault weapons ban, there were roughly 8.5 million AR15 style weapons in the U.S. Now, roughly 20 million.

    1. pgl

      What ban? That temporary 1994-2004 period – right? Or did you mean the expiration of the ban?

    2. King John's Return

      There are currently more than 16,000 firearm manufacturers in the US and more than 56,000 gun shops in the US. Access to guns, semi-automatic rifles and handguns, along with high capacity magazines is the main problem. Time to limit the number of guns a person can own and ban high capacity magazines altogether. Then, let’s limit the number of gun sellers.

      1. Anonymous

        tojo was told

        leave usa alone

        there is a gun behind every blade of grass

        we will keep it that way

    1. pgl

      Another perspective. Did you limited reading even get to this?

      Mass shootings occur worldwide but are a particular problem in the United States. Despite being home to only 5% of the world’s population, roughly 31% of the world’s mass shootings have occurred in the United States. As of 2015, a mass shooting resulting in the death of four or more people occurred approximately every 12.5 days. In addition to public massacres such as the shooting in an Orlando, Florida, nightclub in 2016, these figures include mass shootings related to gang activity or family slayings. Although there are many variables responsible for a mass shooting, and each instance is immediately precipitated by different events, the commonality is that a significant number of individuals are killed during the event.

      The US’s statistics are much worse than your MAGA buddies care to admit. OK contagion may be one issue but they never said it was the only issue. The lack of gun safety laws in this nation can be blamed by NRA nut jobs like you.

      1. Bruce Hall

        Did you actually read beyond the statistics? Of course not. Your beta-minus compatriots are finding their only meaning in life killing others for their 15 seconds of notoriety. The slug in Highland Park was a perfect example of what that article was all about, but you couldn’t get beyond the 2015 and 2016 statistics mentioned in the article which were under whose watch by the way?

        Context, man, context. What was the article all about and why did you miss it?

        1. pgl

          Your reading comprehension skills suck as usual. I did not deny that contagion may play a role but even your own source noted there were other factor. Come on Brucie – relax. We already know you are Trump’s dumbest troll so you do not have to prove it daily.

        2. pgl

          The slug in Highland Park was a perfect example of what that article was all about, but you couldn’t get beyond the 2015 and 2016 statistics mentioned in the article which were under whose watch by the way?

          Wow Brucie did not read or at least did not understand his own link. He did not notice it was a review of the literature with the latest actual research being a 2016 paper. Bruce thinks there is evidence beyond 2016 even though the authors did not present any new research? Yes he is that dumb.

          Now he did not get in another partisan cheap shot at President Obama like there were no murders under Donald Trump. Seriously?

    2. pgl


      Am J Public Health. 2017 March; 107(3): 368–370.
      Published online 2017 March

      Bruce cites a paper published in early 2017 but then he says I cannot get past its 2016 statistics??? Bruce – try reading the entire paper next time as your comments are already stupid enough.

  3. pgl

    Bruce Hall joins his favorite NRA nutcases trying to argue that these murders are not really the fault of lax gun laws. But I will say his heroes are well ahead of Brucie boy in terms of being nutjobs:

    Bimbo Boebert figured out there was ONE such incidence in Denmark so it cannot be the lack of gun laws!

    Marjorie Taylor Greene proves she is even dumber than she is ugly – MAGA politician Rep. Marjorie Taylor Greene, R-Ga., suggested that the attack was part of Democrats’ plans to push forward gun reform.

    WTF? Crimo was working for Pelosi???

    But Tucker fairy man Carlson blamed bossy women:

    The authorities in their lives, mostly women, never stop lecturing them about their so-called male privilege. A lot of young men in America are going nuts. Are you surprised? A shockingly large number have been prescribed psychotropic drugs.

    What is this male privilege Tucker – beating up their wives while shooting up any black man running down the street?

    Now Tucker is nuts along side of Bimbo Boebert and Witch Taylor Greene. Bruce Hall’s heroes!

  4. ltr

    I was trying to convey the fact that the increase in number of mass shooting casualties was not driven by population increase.

    — Menzie Chinn

    [ Precisely and importantly so. ]

  5. ltr

    July 5, 2022

    Life expectancy of Chinese people rises to 77.93 years: NHC
    By Guo Meiping

    The life expectancy of Chinese people has risen to 77.93 years, and the main health indicators are in the forefront among upper-middle-income countries, Mao Qunan, director of the Department of Planning of the National Health Commission, said at a press conference on Tuesday.

    This year marks the third year of implementation of the country’s Healthy China initiative, and China has made remarkable progress in the current stage.

    National databases of experts and resources have been established to promote health knowledge, rational diet, fitness programs and psychological health. The health literacy level of Chinese citizens has improved to 25.4 percent. Major diseases, such as cardiovascular and cerebrovascular diseases, cancers and diabetes, have been effectively contained. Premature mortality from major chronic diseases is now below the global average, said Mao.

    More people have been involved in health activities online and offline, which has laid a social foundation for epidemic prevention and control.

    Promotion of national fitness

    National fitness is one of the 15 actions of the Healthy China initiative….

  6. ltr

    July 6, 2022

    Chinese mainland records 141 new confirmed COVID-19 cases

    The Chinese mainland recorded 141 confirmed COVID-19 cases on Tuesday, with 112 attributed to local transmissions and 29 from overseas, data from the National Health Commission showed on Wednesday.

    A total of 286 asymptomatic cases were also recorded on Tuesday, and 1,951 asymptomatic patients remain under medical observation.

    The cumulative number of confirmed cases on the Chinese mainland is 226,176, with the death toll from COVID-19 standing at 5,226.

    Chinese mainland new locally transmitted cases

    Chinese mainland new imported cases

    Chinese mainland new asymptomatic cases

      1. Barkley Rosser

        Oh my, 4 per million deaths in China due to Covid-19? I have never seen this report before. Are you sure that this is actually correct, ltr?

  7. rjs

    i imagine Menzie must know that the Highland Park shooter was considering a second attack on Madison, but maybe some of you don’t….

    Highland Park shooter charged with 7 counts of first-degree murder; considered second shooting in Madison, Wisconsin
    On the morning of July 6, Highland Park, Illinois, shooting suspect Robert Crimo III confessed to prosecutors he committed a pre-meditated attack on the Fourth of July parade which left seven dead and 46 wounded after firing more than 80 rounds from a rooftop into the crowd. The death toll is subject to change given the severity of the injuries inflicted.
    New details regarding Crimo’s actions before and after the shooting have come to light since he was taken into custody by Illinois police on the night of July 4th. One of the most alarming developments is that Crimo reportedly considered committing a second mass shooting in Madison, Wisconsin, after he was able to evade the police and flee Highland Park. He also dumped his phone in nearby Middleton, Wisconsin, less than 10 miles west of downtown Madison, in an effort to throw the authorities off his tracks.
    According to Lake County Major Crimes Task Force spokesman Sgt. Christopher Covelli, the 21-year-old suspect “seriously contemplated doing another shooting in Madison.” Crimo had a second semi-automatic rifle with him, along with 60 rounds of ammunition as he traveled to the Wisconsin state capital. Sgt. Covelli added that upon entering the city, Crimo “saw a large fest and began considering an attack” but “hadn’t put enough thought or research into it.” Crimo also may have been dissuaded by the poor weather in Madison which at the time included large rolling thunderstorms. It remains unclear which event or festival he was considering attacking.

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