There's a science question here, and there's an engineering question here. They are two different questions.
Science asks, what are the numbers, what are the likelihoods? And there is always going to be more study needed. Consider that people are still arguing over evolution, there may never be numbers so compelling that they convince everyone.
The engineering question asks what we could do to change things. Engineers don't get to wait for better numbers, they have to do the best they can with what they've got. We don't really know why the violent crime rate has been going down for the last three decades, when everyone expected the rate to rise. Was it declining lead levels? Legalized abortion? How much consensus would we need to do more of it?
Lots of focus on fiction media- the videogames and movies that are supposed to be shaping young people's thoughts. I don't see news people asking questions on what effects their own reporting has had on the problem. Roger Eber thttp://boingboing.net/2012/12/15/roger-ebert-on-how-the-press-r.html and Charlie Brooker http://www.youtube.com/watch?v=PezlFNTGWv4 both make a compelling case that it's the way these events are reported that makes their recurrence inevitable.
Ultimimately, i think you have to decide how deeply you want to question these things. James Howard Kunstler http://www.youtube.com/watch?v=Q1ZeXnmDZMQ&feature=youtu.be#t=14m29s points to the architecture we live in as a primary source of dispair. I think he's got a point too.
Mass shootings are not the only symptom that we are doing it wrong. I doubt that it's even the worst symptom of us doing it wrong. They're just a symptom that few would disagree about that something needs changing.
I don't know how to keep this topic away from http://lesswrong.com/lw/gw/politics_is_the_mindkiller/ , so I'm just going to exhort everyone to try to keep this about rationality and not about politics as usual. I myself have strong opinions here, which I'm deliberately squelching.
So I got to thinking about the issue of gun control in the wake of a recent school shooting in the US, specifically from the POV of minimizing presumed-innocents getting randomly shot. Please limit discussion to that *specific* issue, or we'll be here all year.
My question is not so much "Is strict gun control or lots of guns better for us [in the sole context of minimizing presumed-innocents getting randomly shot]?", although I'm certainly interested in knowing the answer to that, but I think if that was answerable we as a culture wouldn't still be arguing about it.
Let's try a different question, though: how would we know?
That is, what non-magical statistical evidence could someone give that would actually settle the question reasonably well (let's say, at about the same level as "smoking causes cancer", or so)?
As a first pass I looked at http://en.wikipedia.org/wiki/List_of_countries_by_intentional_homicide_rate and http://en.wikipedia.org/wiki/List_of_countries_by_firearm-related_death_rate and I noted that the US, which is famously kind of all about the guns, has significantly higher rates than other first-world countries. I had gone into this with a deliberate desire to win, in the less wrong sense, so I accepted that this strongly speaks against my personal beliefs (my default stance is that all teachers should have concealed carry permits and mandatory shooting range time requirements), and was about to update (well, utterly obliterate) those beliefs, when I went "Now, hold on. In the context of first world countries, the US has relatively lax gun control, and we seem to rather enjoy killing each other. How do I know those are causally related, though? Is it not just as likely that, for example, we have all the homicidally crazy people, and that that leads to both of those things? It doesn't seem to be the case that, say, in the UK, you have large-scale secret hoarding of guns; if that was the case, they'd be closer to use in gun-related homicides, I would think. But just because it didn't happen in the UK doesn't mean it wouldn't happen here."
At that point I realized that I don't know, even in theory, how to tell what the answer to my question is, or what evidence would be strong evidence for one position or the other. I am not strong enough as a rationalist or a statistician.
So, I thought I'd ask LW, which is full of people better at those things than I am. :)
Have at.
-Robin