Not sure if they're using that for "mass shootings" as it refers to what they will consider a "serial killing."
I did find this interesting article about the varying definitions, though.
https://www.washingtonpost.com/news/wonk/wp/2016/02/26/we-ha...
> Going back to your "notoriously anti-gun" description. Why does it matter?
It matters to me because when I see them as a source, I know to do a little more legwork and check the sources before sharing the information that they have presented. Mother Jones is one of an unfortunately long list of websites that I don't trust very much. The bright side to that is that it's spurred me to dig further into topics.
A-ha! Found it! The bill which changed it was the Investigative Assistance for Violent Crimes Act of 2012, 28 USC 530C(b)(1)(M)(i), https://www.gpo.gov/fdsys/pkg/PLAW-112publ265/pdf/PLAW-112pu... and the law text is at https://www.law.cornell.edu/uscode/text/28/530C :
> For purposes of this subparagraph — (I) the term “mass killings” means 3 or more killings in a single incident; and (II) the term “place of public use” has the meaning given that term under section 2332f(e)(6) of title 18, United States Code.
It looks like Mother Jones is using the current federal definition.
Agreed, just because there is a definition doesn't mean it's a good definition. The idea that 18 people can be shot but only one killed should still make it be a mass shooting, but the FBI wouldn't count it. That's the argument given https://www.massshootingtracker.org/about , which uses a different definition to conclude there have been "1306 mass shootings since 1/1/2013"
Does feedback like this help you adjust your confidence levels? That is, might you think better of a Mother Jones analysis in the future, or give you less reason do the legwork?
While on the other hand, this op-ed piece appears to have undercounted the numbers, and for unspecified reasons uses "the traditional FBI definition" rather than the current FBI definition. (I, and perhaps you also, thought he was using that phrase to mean something like 'the current and long-held definition', not 'the older definition, which I prefer').
Does that make you less likely to trust the general argument?
Whether it is a good definition or not is important, but you're not focusing on the salient fact: the definition was changed, recently, which makes it difficult to compare current data with older data.
"for unspecified reasons uses "the traditional FBI definition" rather than the current FBI definition."
Perhaps because he wants to actually compare the rates over time without talking nonsense.
At some level the cutoff for what constitutes a "mass shooting" is fuzzy. That doesn't make it okay to do a straight comparison of data that uses one definition with data that uses another definition.
The salient question is, given the data - no matter what definition is used - does the analysis make sense?
I gave a link to a page which goes into that more carefully, and concludes that a simple average, as the editorial author did, does not make sense.
This question about the definition is a side-issue. The fact that I cannot reproduce the numbers does make me wary, but even if it were correct, the conclusion drawn from that data is simply false.
One way to improve the confidence of the data, without more sophisticated statistical analysis, is to increase the baseline. He already has a much longer baseline for US data, and he elsewhere complained about the arbitrary time definition for an FBI report which he said artificially skews the results.
Why then did he choose the first 7 years of Obama, and not 20-30 years?
Okay, let's define "mass shooting" to include people who are shot wholesale by government action (by the way: why shouldn't it?), and increase the time frame to 75 years.
Now compare the U.S. to Europe, and your conclusions about the relative rates will be...somewhat different.
The Netherlands lost about 2% of its population in WWII, the equivalent of about 7 million deaths in a population the size of the current United States.
I said "just because there is a definition doesn't mean it's a good definition". That doesn't mean I think it's a good definition or a bad definition. I personally prefer the definition used by massshootingtracker.org, which concludes there have been 1300+ mass shootings since 2013. However, I also think someone will argue about any reasonable definition.
I also said "It doesn't matter that the federal definition changed a couple of years ago." That doesn't mean I think any definition will work, only that for the purposes of this analysis, we can choose either the old definition or the new one - or any reasonable definition.
I'm willing to accept the old definition and focus on the real "salient", to use your term, issue, which is that the results of this op. ed piece are worthless, because of poor use of statistics.
Take your time.
If anything, it says that mandated arming of large numbers of citizens (conscription), and mandatory use of such weapons, leads to a higher number of mass killings.
That's a different conversation than the mandated disarming of large numbers of citizens.
Translation: it wouldn't fit the political agenda of the op. ed piece.
Buh-bye.
They use the new (since 2014) definition of 3 deaths. Here's the relevant law: https://www.law.cornell.edu/uscode/text/28/540B .
You are correct - the Mother Jones table does include the killer, if the killer also died. I checked the killings with 4 deaths. The suspected coffee shop police killer was killed by police at another time, and the Alturas tribal shooting killer was arrested. The killings with 5 and 6 deaths were all done by a single person.
So that doesn't explain the discrepancy.
The editorial author believes the new definition was done for political reasons, and prefers to use the older one. See http://nypost.com/2014/10/12/the-fbis-bogus-report-on-mass-s... for another op-ed by the same author.
You'll note that the author has "data on [US] mass public shootings from 1977 to 1999." Why, I wonder, did the author only report on a 7 year baseline, rather than 40 years? That longer baseline would help with the regression to the mean problem intrinsic to this analysis. He's had years to do that.
His NY Post piece even chides the FBI for using a too-short baseline since the early 2000s had a fewer than average number of killing.
Going back to your "notoriously anti-gun" description. Why does it matter? Mother Jones gave all of their data, with links to the primary source for verification. My cursory spot check found no discrepancies.
Since the editorial author appears to be "notoriously" pro-gun, given his book and op-ed pieces, but doesn't give the full data or explain the choice of baseline - and does a poor job of interpreting the numbers - shouldn't those conclusions be even more suspect?