"If mass shootings are really occurring at random, then this suggests that they are extreme, unpredictable events, and are not the most relevant measure of the overall harm caused by gun violence."
In my Undergrad years I would get crucified for arguing that a computational model works and concluding that it is therefore the way reality works.
Seriously though, can anyone reading this fathom a way to formalize the event "Guns are available"? What's the probability of getting a gun if it's not available in shops? You need to model a different country for that.
The same reasoning can be used to show that the probability of a mass shooting given the availability of guns is lower given a lack thereof. In other words, this: http://www.youtube.com/watch?v=KsN0FCXw914 .
And if they are indeed rare events, what's the metric for that? If we have a chance of stopping a rare, unexpected event that would add quite a lot to the expected value of deaths per year, would it not matter significantly in our efforts of stopping it?
I don't think the author is attempting to imply anything other than "Assuming mass shootings are random unrelated events, 7 mass shootings in 1 year does not necessarily signal a significant change from the past 30 years. (Though if it happens again, it does.)"
I thought so too until I read the last 3 paragraphs. "Those numbers check out" is totally valid. But concluding with the relevance of the measure of gun harm is an observation about reality, not Statistics, which is debatable, but has no relevance to what was previously mentioned.
We haven't yet defined the goals. Unless "Minimum amount of gun-related deaths" is the goal (clearly, it isn't that simple in this country), in which case his highlighted claim is definitely false - we don't know much about effective metrics. Are the psychological effects of a mass shooting similar to a snowball effect? Maybe in the long run? There's a lot more to research before saying 'insignificant', especially if you don't describe the model.
One more thought: could you define 'mass shooting'? Usually the media is responsible for that definition, whereas a random murder isn't called that.
The conclusion about the relevance of the measure of gun harm seems to me the "mass shootings in 1 year does not necessarily signal a significant change from the past 30 years" part. It means that discussions along the line of "Why the change?", or "How can we go back to the way it was before?" are premature, though it does not say anything at all about discussions along the line of "How do we reduce mass shootings?".
Mother Jones probably did a pretty decent job of defining 'mass shooting', I assume they errored on the side of inclusion (I only recall 2 this year). The authors analysis seems to make it pretty clear it is only considering that definition.
I'm really not reading this as an attack on discussions of gun violence in general, as it seems you are.
> If we have a chance of stopping a rare, unexpected event that would add quite a lot to the expected value of deaths per year, would it not matter significantly in our efforts of stopping it?
I wouldn't characterize the number of deaths via mass shootings as "quite a lot". It's probably in the same ballpark as death by lightning strike (~50/year, according to Wikipedia).
Seriously though, can anyone reading this fathom a way to formalize the event "Guns are available"? What's the probability of getting a gun if it's not available in shops? You need to model a different country for that.
The same reasoning can be used to show that the probability of a mass shooting given the availability of guns is lower given a lack thereof. In other words, this: http://www.youtube.com/watch?v=KsN0FCXw914 .
And if they are indeed rare events, what's the metric for that? If we have a chance of stopping a rare, unexpected event that would add quite a lot to the expected value of deaths per year, would it not matter significantly in our efforts of stopping it?