To a certain extend it makes sense that more readily available guns cause more shootings, but I highly doubt that it's a simple linear relationship.

If I don't have access to a gun I can't go on a rampage shooting. If a friend of mine has a gun I could go on a rampage shooting, but I'm probably less likely to do it on impulse. If anybody in my household owns a gun I can likely go on a rampage shooting whenever I like. But if I own 10 guns I don't see how that makes a rampage shooting any more likely.

The proper statistic would be rampage shooting per household with at least one gun. But even that's probably still very flawed (are dangerous people more likely to own guns?)

In the USA, people who own guns are likely to own more than one gun. They may be hunters or collectors. Per-gun is fairly meaningless.

I recently read statistics that the number of households owning guns has decreased from 50% to ~30% since 1977, while the number of guns increased over that time period.

I did some back of the envelope checks on those statistics, and they would require us gun owners to have arsenals worth $100,000 or so.

Note that one's willingness to tell an anonymous voice on a phone that one owns guns changes with the political climate towards guns.

How do you get $100,000? If 30% of households own guns, that's about 37 million gun-owning households. If there are 300 million guns, that's about 8 guns per gun-owning household. If that's $100,000, that means a gun is worth on average $12,500. I'm hardly an expert on guns but that seems about an order of magnitude too high from what I do know.

This was in reference to a statistic about who's buying newly manufactured "assault weapons", particularly the mass quantities of AR-15 pattern rifles and the like that have been selling like hot cakes since the 2008 election.

It insisted that only us "gun nuts", not e.g. the large number of households that only have one or two guns for self-protection, were buying almost all of these new guns; to review and improve my estimate we'd have to find that particular statistic/study.

I see. Is there some context in the gun world that I'm missing out on? Since the comment you replied to said nothing about AR-15s or indeed anything beyond the number of gun-owning households and number of guns overall changing over the years.

The economics of firearms look a lot more like ham radio where a lifetime of "trading up" and selling for about the cost of purchase result in some interesting statistics, for older people anyway. Very few 20 year old kids have a $10K gadget, however, 60 year olds are another story.

Also there are occasional rashes of criminals with phone # to address database access surveying people for firearm and jewelry ownership. Even "innocent" corporate or written/mailed survey data can be assumed to be entered in a computer and that means it is only a matter of when, not if, it'll be stolen/hacked. So if someone has no need to know whats in my safe (aka, absolutely everyone other than immediate family members) then the only intelligent answer about the contents of my safe is no, I own no guns, no collectible coins, no jewelry, and I keep no cash on hand other than $20 in my wallet, and I have no idea why I'd ever tell anyone any other response.

The number of households who answer in the affirmative when asked by pollsters has certainly dropped in that time period.

I have serious doubts that the actual number of gun owning households has dropped that much.

The problem here is that you're assuming there's a correlation between guns per capita and shootings per capita, which is similar to the (potential) fallacy that the OP made: that there's a correlation between gun restriction laws and shootings per capita.

Why is the USA then the extreme outlier then when it comes to the sheer number of shootings also highest concentration of guns anywhere in the developed world?

Correlation does not imply causation. As noted elsewhere in this discussion, there are plenty of other potentially relevant correlations, and as also noted, if you cast the net wider than the ODEC we no longer are an "extreme outlier".

I'm not sure how we've deluded ourselves into thinking that the two are not directly related. As other commenters have mentioned, it isn't big scary guns, but the hundreds of millions of handguns everywhere and easily available in the USA that do most of the damage.

See where I just commented on the fact that our murder rate has halved since the 1970-90s period while gun ownership rates have not changed, strongly suggesting we should look elsewhere, perhaps, as I note, demographics: https://news.ycombinator.com/item?id=9838517

The murder rate overall has gone down, but we are still an outlier when it comes to the number of guns and gun homicides.

This is a strange definition of correlated, where one variable changes and the other does not.

Our outlier high gun homicide rate is dependent on our extremely high number of guns easily available to commit those homicides.

So you're saying these two variables are correlated, even though they are not, in fact, correlated?

They are correlated.

Who's on first?

Perhaps people afraid of being the next shooting victim buy lots of guns.

I have a lot of guns, and I know lots of people with lots of guns.

None of us buy them beause we're "afraid of being the next shooting victim".

Ah, so per resonators comment, you must have bought them because you want to be the the next shooting perpetrator.

Russia's murder rate is twice that of the United States yet their gun laws are far more restrictive. Mexico's murder rate is also about 4 times higher than the United States even though there's literally only 1 legal gun shop in the entire country.

I would wager that a lot of violence in the US is caused by the drug war. Mass shootings are more common than they should be but they're a drop in the bucket compared to all of the violence created by the drug black market.

But drug violence has plummeted from its high point. The drop in drug prices (engineered by the CIA?) meant folks no longer want to get killed over $50.

The drop in drug violence could be a couple of different things but if it is correlated with a drop in prices that would suggest that decriminalizing or legalizing would further drop violence. Just like it did with the end of prohibition.

I don't know.

That's the point: a lot of us, including the article's author, are attributing causes to the amount of spree shootings along to the amount of deaths caused by firearms in general to several individual phenomena but there's almost no way of controlling for a myriad of other factors in play, which include very diverse things like culture, political climate and demographics.

Do these counts of the number of guns include the number of illegally held guns as well?