Kevin Drum

Lead and Crime: Some New Evidence From a Century Ago

| Sun Jan. 4, 2015 10:48 AM EST

And now from the future to the past: specifically, the period from 1921 to 1936. Let's talk about homicide.

James Feigenbaum and Christopher Muller recently published an intriguing paper that looks at the correlation between the introduction of lead pipes in American cities at the turn of the 20th century and the increase in the murder rate 20 years later. Southern cities, it turns out, mostly opted out of lead piping (mainly because they lacked nearby lead smelters and refineries), so F&M present separate results for northern and Midwest cities where the vast bulk of lead pipe construction took place.

Their basic results are on the right. Cities with at least some lead piping had murder rates that were, on average, 8.6 percent higher than cities with galvanized iron or wrought iron pipes. Other causes of death were mostly unrelated. Only the murder rates changed1.

Now, there are several things to say about this. On the positive side, this study avoids some of the confounding factors of other studies. Lead paint and gasoline lead, for example, tend to be concentrated in poor neighborhoods, which means that correlations with crime might be due to hyper-local socio-geographic factors rather than lead itself. But F&M's study avoids this problem: lead piping generally served entire cities, so it affected everyone equally, not just the poor. And since the likelihood of using lead pipes was mostly a factor of how close a city was to a lead refinery (thus making lead pipes cheaper), there's no special reason to think that cities which used lead pipes were sociologically any different from those that used iron pipes.

On the negative side, it's risky to look solely at homicide numbers. This is because the absolute number of murders is small, especially on a city-by-city basis, and that means there's a lot of noise in the numbers. This is especially true when you're limited to a period of time as short as 15 years. There's also the fact that this was an era when lead paint was widely used, and that's very hard to tease out from the use of lead in pipes. Finally, there's the usual problem of any study like this: what do you control for? The use of lead pipes is plausibly unrelated to anything else related to crime, but it's impossible to know for sure. The authors do control for black population, foreign-born population, occupations, home ownership, and gender breakdown, and that reduces their effect size from 11.4 percent to 8.6 percent. Might some other control reduce it even further?

Plus there's the anomaly of Southern cities. Very few of them used lead pipes, but some did, and their murder rates were essentially no different from any other Southern cities. Why? It's possible that this is because their use of lead pipes was small (F&M have data on lead pipe use by city, but not on how much lead piping was used in each city). But it's still odd.

Finally, there's a fascinating aspect to this study: when you study lead and crime, you need to concentrate on young children, since they're the ones primarily harmed by lead exposure. So you want to correlate lead exposure to crime rates 20 years later. As near as I can tell, F&M do this, but only by accident: their lead pipe data comes from 1897 but the earliest reliable homicide data starts in 1921. So the proper time lag is there, but it doesn't appear to be deliberate. They do mention the time lag briefly in their discussion of a confirming bit of evidence toward the end of the paper, but nowhere in the main body.

In any case, this is yet another small but persuasive bit of evidence for the link between lead exposure in children and increased rates of violent crime when those children grow up. Despite the study's few weaknesses, it really is plausible that lead piping is exogenous to any other factor related to crime rates, and this makes F&M's discovery pretty credible as a causal factor for the difference in murder rates between lead-pipe and iron-pipe cities, not just a spurious correlation. Interesting stuff.

1Actually, not quite. They tested for cirrhosis, suicide, heart disease, pneumonia, tuberculosis, auto accidents, influenza, diabetes, childbirth, syphilis, whooping cough, measles, typhoid, scarlet fever, train accidents, and malaria. All were uncorrelated except for cirrhosis and train accidents. The latter two are unexplained, though lead exposure actually is related to cirrhosis, and it's possible that reductions in impulse control might lead to more train accidents. Still, a bit odd.

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A Quick Note About the Future

| Sun Jan. 4, 2015 9:55 AM EST

Jus a quick note before I move on to another subject this morning. A fair number of comments to my list of predictions yesterday suggested that it made for pretty depressing reading. But I suspect that might have been due to my tone more than the actual content of the predictions themselves. There's a bit of fuzziness here, but here's how I'd classify them:

  • Basically positive: 1, 2, 5, 9, 11, 13
  • Neutral-ish: 4, 8, 10, 14
  • Basically negative: 3, 6, 7, 12, 15, 16

Obviously there's room for debate here. For example, I count the development of artificial intelligence (#1) as a positive development, but I do concede that it will either "transform or destroy" the world. (The case for destroying the world is here.) On the neutralish side, you might think that super social media (#8) sounds great, not neutral, and if you're Russian or Chinese you won't think much of #14. On the negative side, the stagnation of manned space travel (#12) might strike you as a yawn, and although any kind of biological attack is bad (#16), I pretty much think we'll be able to contain this threat.

In any case, you can argue about my categories. Still, I think by any fair measure I ended up with a roughly an even mix of good and bad, and that's just the way the world is. If you made a similar list for 1900-1950 but did it in hindsight, you'd get electrification, mass-produced cars, and penicillin, but you'd also get the Great Depression, two massive world wars, the start of the Cold War, and the invention of nuclear bombs. It was hardly all roses.

I suspect that for most of us alive today, our attitudes are skewed by growing up in the period from 1950-2000. But this is the anomaly: obviously there was some bad stuff during this era, but the good far outweighed it. On a broad scale, it was almost certainly the most progressive and innovative half-century in human history. After all, we might have been bristling with nuclear weapons, but we never ended up using them, did we? And we made massive material and social progress around the globe, but didn't yet have any big worries about climate change or terrorism. In hindsight, most of our fears turned out to be modest, while our progress was unprecedented. It's possible that the period from 2000-2050 will repeat that, but at the very least I think the dangers of the next few decades are both real and deserve consideration.

For what it's worth, though, virtually everything hinges on two things: the development of benign artificial intelligence and the development of clean, abundant energy. If we manage those two things, the world will be bright indeed.

16 New Year's Predictions That Are Not For 2015

| Sat Jan. 3, 2015 11:34 AM EST

I'm up early (thanks, dexamethasone!) and there's not really any news in the morning papers that I'm just bursting to respond to. So, since predictions are the thing to do when a new year dawns, here are some predictions. Not for 2015, mind you—I'm not an idiot—but for the medium-term future, which in my book extends over the next 30 years or so for reasons given in prediction #1. Here you go:

  1. AI and robotics will continue to improve rapidly. We'll have useful AI by 2025 and full AI by 2045. This will either transform the world or destroy it. Flip a coin. However, regardless of how the end point turns out, the transition period is going to be pretty brutal for the 90 percent of the population that occupies the middle classes and below. Note that this prediction is #1 on my list for a reason. The rest are randomly placed.
  2. At some point, we will reach a tipping point and medicine will be revolutionized. I'm guessing it starts around 2025 and really takes off over the ensuing decade or two. By 2030 or so nanobots will be involved. I know this has been predicted for about as long as nuclear fusion reactors have been "twenty years away," but honestly, that's not a strike against this prediction. It just means that lots of influential people are habitually starry-eyed about technology, something that's always been true for reasons of either personality or simple business self-interest. But the medical revolution will come regardless. It will just take longer than the congenital utopians thought. Speed bumps along the way aren't reasons for cynicism, they're the signposts of progress.
  3. Climate change is going to start to seriously bite by 2030. This will have increasingly catastrophic results in equatorial zones, which rich countries will decline to do much about despite many pious promises. We'll be too busy adapting ourselves.
  4. However, the big wild card on climate change is geoengineering. I think there's at least a 50 percent chance that we'll undertake some kind of major geoengineering project by 2035, either unilaterally or as a global initiative. It will almost certainly be something of a clusterfuck, but we'll get better with experience and the continued development of AI.
  5. On the bright side, solar panels will keep getting cheaper. By 2020 they'll be competitive with coal in many parts of the world. As early as 2030, solar could be providing a very substantial part of our energy production if we have the brains to get serious about reducing greenhouse gases and allow government regulation to speed the process of the free market. Unfortunately, I don't have much faith that we'll do this. But if we do, it will allow us to start our geoengineering experiment with more modest projects, which will be a very good thing indeed. Nuclear fusion remains unlikely but not impossible.
  6. The rich world will continue to age. Old people will continue to vote in large numbers. This will reach a critical point around 2025 or so, but I don't really know how it's going to resolve itself. Maybe we'll just muddle along. Maybe old people will increasingly—and successfully—demand policies that steadily kill economic growth. Maybe the young will revolt. I'm just not sure.
  7. The surveillance state will continue to grow. Partly this is because technology simply can't be stopped, and partly because terrorism will continue to increase and we will willingly trade privacy for security. By 2030 personal privacy will be all but dead, and everyone under 40 will simply accept it. The rest of us will remain uncomfortable but won't put up much of a fight.
  8. Social media as we know it will slowly die out. It will be replaced by (a) ubiquitous surveillance, (b) instant, ubiquitous wireless communication, and (c) immersive virtual reality. This will happen in the rich world by, say, 2030, and in the rest of the world a decade or two later.
  9. Online retail will continue to grow. Duh. Partly this will happen for the obvious reasons, partly because the experience of truly trying out a new product online before you buy will get better and better. The kindergarten version of this is reading a sample of a book for free before you buy. The grownup version will be virtual versions of tech gadgets that you can play with as if they were in your hands, along with highly accurate online avatars that will let you try on virtual clothing and truly see what it looks like and whether it fits. Here in Irvine, a nearby shopping center is slowly being shut down and transformed into a medical office complex. I take this as a sign of things to come.
  10. Personal 3D printing? I'm still not sure if and when that becomes more than a toy. At an industrial level it will certainly become a big thing, allowing us far more routine customization of consumer products that we buy online.
  11. Real, honest-to-god driverless cars that can navigate essentially anywhere and respond to sophisticated voice commands, will become reality by 2025 or 2030. See #1 for why. This will change society as profoundly as the invention of the mass-market car itself.
  12. Manned space exploration will go nowhere. We will not colonize the moon. At most, we will eventually launch a manned mission to Mars, but it will find nothing of interest beyond what unmanned probes have discovered. We gave up on manned missions to the moon after seven flights. We'll give up on Mars after one or two. FTL travel will continue to be impossible. Thanks a lot, Einstein!
  13. We will all have plenty of body implants by and by. Bionic eyes are an obvious possibility. Bionic limbs are already good enough that their continued success barely counts as a prediction anymore. Cognitive enhancement will become mainstream, which is a good thing since we'll need it to keep up with AI development.
  14. Russia will decline. China will keep growing and will certainly become a major world power, but growth will slow down due mostly to inexorable consequences of demographics and the decay of labor costs as a competitive advantage. Over the long term, the United States will continue to outperform them both, as well as the EU and (maybe) South America. I'm not really sure about India.
  15. Nuclear warfare? Beats me. I'd say a major exchange is unlikely, but a few minor exchanges are certainly possible. The most likely spot is the tinder keg stretching from Morocco to India, which already contains three nuclear powers and will likely contain at least two more (Iran and Saudi Arabia) within two decades.
  16. There will also be some terrorist biological attacks, but nothing catastrophic. Thanks to ubiquitous surveillance and superior technology, the good guys will develop defenses faster than the bad guys can develop truly killer bugs. Whether the same can be said for natural pandemics is less clear.

As you've noticed, I have no predictions for art or culture, which I know little about. In any case, these subjects are far too nonlinear to say anything useful about. Not too much about politics either, though the political implications of many of the predictions are fairly obvious. Economics will undergo a sea change for the same reason it's gone through sea changes before: the underlying world of trade and money will fundamentally change. It's not clear if the political class will pay much attention to this, but at some point I suppose they won't have much choice.

The corporate world, despite the endless predictions of the techno-utopians and the equally endless kvetching about slacker Millennials, won't really change much. There will be more telecommuting, more consolidation into gigantic multinationals, and ever more sophisticated marketing, but no revolutionary changes to the basic structure of business. (The marketing part of this prediction relies largely on the fact that although big data may look like crap right now, it won't forever, and it will intersect with ubiquitous surveillance to become either revolutionary or sinister depending on your worldview.) Patent law will either be seriously reformed or will become perhaps the most dominant and most oppressive feature of corporate R&D. Not sure which.

Media will continue to be 95 percent entertainment subsidizing a small amount of serious news, just as it's been for centuries. Only the tech will change. Books will continue to be books. English will continue to take over the world (see #14), though it's possible the development of accurate, idiomatic, real-time translation AI will make this a moot point. The revolution of medical tech may or may not come soon enough to affect the treatment of multiple myeloma.

Obviously I'm missing lots of stuff. Some of it is due to ignorance, some is because I'm genuinely skeptical that certain much-hyped trends are likely to pan out. However, I'm not going to tell you which is which. This will allow me to plausibly deny ignorance for anything big that I've stupidly left off my list.

You should feel free to offer to bet me on any of these trends, but they're all far enough out that you'll likely have to badger my estate for payouts. Good luck with that. This is deliberate on my part, so let's skip the whole betting thing, OK?

Friday Cat Blogging - 2 January 2015

| Fri Jan. 2, 2015 3:10 PM EST

Let's start off 2015 right. Today Hilbert gets catblogging all to himself. Why? Because he's just that magnificent, that's why. This is sort of a reverse-selfie, the kind of picture Hilbert would take if he didn't have a servant to take it for him. But he does. Life is good.

Of course, he doesn't quite have catblogging all to himself. Hopper is back there waiting her turn. How did she manage to photobomb this picture? That's easy. Around here, if you just point a camera randomly in any direction, you have at least even odds of a cat showing up. This is the sign of a properly run household.

There's More to the Oil Collapse Than Just Shale

| Fri Jan. 2, 2015 2:37 PM EST

Bloomberg provides us today with the following chart of oil prices over the years:

James Pethokoukis has a complaint:

There is one major factor affecting oil prices that somehow got left out. Really, nothing on fracking and the shale oil revolution? Granted, it’s not an event easy to exactly date (though somehow the accompanying article manages the trick), but neither is China’s economic takeoff, and that got a shout-out.

It's a fair point—but only up to a point. Keep in mind that US shale oil production has been growing steadily for the past five years, and during most of that time oil prices have been going up. It's only in the past six months that oil prices have collapsed. Obviously there's more going on than just shale.

James Hamilton, who knows as much about the energy market as anyone, figures that about 40 percent of the recent oil crash is due to reduced demand—probably as a result of global economic weakness. Of the remainder, a good guess is that half is due to shale oil and half is due to the OPEC price war in Bloomberg's chart.

In other words, although US shale oil production is likely to have a moderate long-term impact, it's probably responsible for a little less than a third of the current slump in oil prices. The rest is up to OPEC and a weak economy. So give shale its due, but don't overhype it. It's still responsible for only about 5 percent of global production.

Supreme Court Set to Devastate Millions of Lives Later This Year. But Will They Pull the Trigger?

| Fri Jan. 2, 2015 1:15 PM EST

Greg Sargent notes that the future of Obamacare is one of the big political unknowns of the new year:

One of the big, looming questions of 2015 is this: Will the Supreme Court really gut Obamacare subsidies in the three dozen states on the federal exchange, potentially depriving millions of health coverage at a moment when the law, now heading into its second year, is clearly working as intended?

One thing to watch as we approach the SCOTUS hearings on King v. Burwell this spring is how many people are newly qualifying for subsidies in those states as this year’s enrollment period continues....We could be looking at a lot of people who would lose subsidies in the event of a bad SCOTUS ruling, perhaps more overall than previous estimates of around four million. And the enrollment period still has six weeks to go.

I've guesstimated previously that around 6 million would be affected in 2016 if the Supreme Court kills subsidies on the federal exchange later this year. Charles Gaba figures it's somewhere around 5-6 million this year. That's a lot of people who would face one of two things: (a) an increase of maybe $2-5,000 in their health care premiums, or (b) an end to health care coverage completely because they flatly can't afford the unsubsidized premiums.

Will this affect the court's thinking? It's hard to think of a comparable case where a ruling would have had such an immediate, devastating effect on millions of ordinary people. If anything, that gives me hope. Will John Roberts and Anthony Kennedy really be willing to inflict that kind of real-world pain, regardless of their ideological convictions? Maybe not. At least, I hope not, because I've basically given up on the idea that the Supreme Court is anything other than crudely results-oriented these days. Especially on the conservative side of the aisle, they simply don't seem to care much about law or precedent or common sense anymore. They like what they like and they hate what they hate, and they shape their opinions to match.

Maybe that's just the despair of a liberal who's seen a lot of cases go against him over the past few years. Maybe. But I guess we're going to find out later this year.

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Our Obsession With Mass Incarceration May Finally Be Ebbing

| Fri Jan. 2, 2015 12:01 PM EST

Atrios has a New Year's wish:

My hope is that the tide continues to turn (it has, I think, if slowly) against the mass incarceration project this country has been engaged in for decades. It isn't that I wasn't aware of it as a problem before, it's that I now have a much greater sense of how it's the nexus of a whole system of racist horror. Let's fix it.

This is a very reasonable wish. It's important to realize that the huge boom in prison construction and mandatory sentencing laws of the 70s and 80s was a response to a real thing: the massive increase in violent crime during the 60s and 70s. It's almost a certainty that we overreacted to that rise in crime and incarcerated too many people in response. Still, it wasn't just an irrational panic. Violent crime really did skyrocket during that era, and fear of victimization was both palpable and legitimate. That made a big increase in the prison population inevitable.

Needless to say, that's changed. Violent crime has plummeted by an astonishing amount in the past two decades. It takes a long time for public perception to catch up to changes like this, but it does catch up eventually—and as the fear of crime eases, the lock-em-up mentality of 40 years ago has started to ease along with it. In addition, there are simple demographics at work: if there's less crime and fewer arrests, there are simply fewer criminals to lock up. Long sentences from an earlier era have kept prison populations high despite this, but eventually even that has begun to fade away.

In other words, in the same way that mass incarceration surged because of a real thing, it's finally starting to ebb because of a real thing: the actual, concrete decline in violent crime that started in the early 90s and which appears to be permanent. America is simply a safer place than it used to be, and looks set to stay that way.

Our prison population is still gigantic by any measure, and there are vast inequities in who gets locked up and how they get treated. But for those of us who'd like to see this problem addressed, at least there's a decent tailwind helping us out. It's not crazy to think that the next decade could see some real changes in the American attitude toward the mass incarceration society we've constructed.

Why Did the Enclosed Mall Die?

| Fri Jan. 2, 2015 11:00 AM EST

Alex Tabarrok links today to a BBC piece on the death of the American shopping mall. But it's really about the death of the enclosed American shopping mall. So why did enclosed malls go the way of the dodo starting in the early 90s? Here's the author's crack at an explanation:

When the 35-year-old Cloverleaf Mall in Chesterfield, Virginia, closed in 2007, the Chesterfield Observer noted that while it had been a popular hangout for families in the 1970s and '80s, “That all changed in the 1990s. Cloverleaf’s best customers, women, began staying away from the mall, fearful of the youth who were beginning to congregate there. People [said a former Cloverleaf manager] started seeing kids with huge baggy pants and chains hanging off their belts, and people were intimidated, and they would say there were gangs.”

OK.  How about Amy Merrick in the New Yorker earlier this year? What does she think?

As any cubicle dweller knows, people like natural light and fresh air and, when deprived of them, feel oppressed. So are people alienated by those older malls, with their raw concrete, brutalist architecture and fretful, defensive air? Developers have a shorthand for this style: the “classic graybox.” In his talk, [Rick] Caruso flashed grim photos of their façades. He lingered on a picture of a deserted food court; you could practically smell the stale grease. “Does this look like the future to you?” he asked.

Here's Neil Howe in USA Today:

There is a generational story behind what's happening to shopping malls. And if you want to know how it will end, you have to pay attention to each generation's role....What most impressed the G.I.s (and the Silent Generation who succeeded them) about malls was their enormous efficiency....Then came suburban Boomers, who grew up with these newly minted malls as kids. As they matured, many Boomers soured on what they regarded as the soulless and artificial consumerism of malls and began to champion what business author Joseph Pine calls the "experience economy" — turning stores and restaurants from mere retail outlets into places that mean something (think Rainforest Cafe or Build-a-Bear Workshop or L.L. Bean). That thinking not only inspired more stores to include a "tourism" component, but it also drove the surging popularity of lifestyle centers in the early 1990s.

....But Xers soon changed the mall scene. This strapped-for-cash generation helped popularize "category killers" and was the first to adopt online shopping. Millennial teens who arrived in the late 1990s began to show less interest in malls in part because their parents deemed malls too dangerous.

The lack of reasonable explanations suggests that nobody really knows the answer. It certainly remains a mystery to me. There's no question that shopping spaces of all kinds have been hurt in recent years by the rise of online retail, and that mall development in particular was hurt by the Great Recession. But the switch away from enclosed malls began in the 90s, and it wasn't because people were tired of shopping. Nor was it because suburbs started to die. It was because enclosed malls were replaced by outdoor "power centers" and "lifestyle centers."

But why? I still don't know. Is it due to the decline of traditional department stores, which served as anchors for enclosed malls? Are stores like Target and Best Buy simply unsuited to be anchors for enclosed malls? Is it cheaper to build outdoor malls? Was it really because people started to see malls as dangerous, as two of the stories above imply?

And how does this play out in less temperate climes than Southern California? No new enclosed mall has been built near me since (I think) 1987. That's not too big a deal, since even in winter it's no chore to shop at an outdoor shopping center. But what about in the suburbs of Chicago? Or Detroit? Or Kansas City? Do people really want to shop at outdoor lifestyle malls when it's ten below zero? Do enclosed malls make a sudden comeback when the weather is bone-chillingly cold and then die again in the spring? Or what?

Perhaps this is just one of those mysteries: consumer tastes changed in the early 90s, and they changed because that's what consumer tastes do. Radio Shack used to be pretty popular too.

Still, it's an interesting mystery. I wish there were a good explanation, not just a few obvious guesses that amount to little more than a shrug of the shoulders. Why did enclosed malls die? Somebody needs to come up with a definitive answer.

POSTSCRIPT: One thing I should note is that although few (no?) new enclosed malls are being built, older malls that have been shut down don't all turn into the infamous dead malls that have gotten so much attention lately. A fair number of them are renovated and reopened. I'm not sure what, if anything, that means. Just thought I'd mention it.

Happy End of the Year!

| Wed Dec. 31, 2014 8:44 PM EST

For many reasons—some that you know about, others that you don't—2014 has been, let's say, a less than ideal year in the Drum household. So nobody here is bidding 2014 a fond farewell. More like a kick to the curb, with the hope that 2015 can hardly help but be better.

So that's that. Goodbye 2014. Don't let the door hit you on the way out. And in fairness, it wasn't all bad, as the photo below shows. This is what our new furballs do to cardboard scratching pads. For 2015, perhaps we'll buy them a nice fresh one to shred to pieces.

NYPD Slowdown Not Likely to Tell Us Much About Broken Windows

| Wed Dec. 31, 2014 2:19 PM EST

As long as we're talking about crime today, the New York Times reports that the NYPD's slowdown in citing people for minor violations doesn't appear to be doing any harm:

In the week since two Brooklyn officers were killed by a man who singled them out for their police uniforms, the number of summonses for minor criminal offenses, as well as those for parking and traffic violations, has decreased by more than 90 percent versus the same week a year earlier, and felony arrests were nearly 40 percent lower, according to Police Department statistics.

....Yet reports of major crimes citywide continued their downward trajectory, falling to 1,813 from 2,127 for the week, a nearly 15 percent drop, according to Police Department statistics.

Mike the Mad Biologist thinks this might be a useful natural experiment:

Here’s the thing: this might not be like the sanitation workers strike. Then, it was obvious what the consequences were—mounds of rotting garbage. But what happens if, after a couple weeks of slowdown, there’s no uptick in violent or property (i.e., breaking and entry) crime? That would undermine the current policing philosophy of the NYPD (and many other cities)....If violent crime doesn’t increase, then arresting people for minor violations doesn’t seem like a good strategy.

Helluva experiment. Let’s see what the outcome will be.

Unfortunately, I doubt that this will tell us anything at all. The timeframe is too short and there are too many other things going on at the same time. Crime statistics have a ton of noise in them, and it's hard to draw any conclusions even from a full year of change. You need years of data, preferably in lots of different places. A few weeks of data in one place is basically just a null.

So....yes, it's potentially an interesting experiment. In real life, though, it's not. It's just a howl of protest from the police that will tell us little about anything other than the state of relations between City Hall and the NYPD.