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Crime Reduction Linked To Lead-Free Gasoline
Hugh Pickens writes "Even low levels of lead can cause brain damage, increasing the likelihood of behavioral and cognitive traits such as impulsivity, aggressiveness, and low IQ that are strongly linked with criminal behavior. The NYTimes has a story on how the phasing out of leaded gasoline starting with the Clean Air Act in 1973 may have led to a 56% drop in violent crime in the US in the 1990s. An economics professor at Amherst College, Jessica Wolpaw Reyes, discovered the connection and wrote a paper comparing the reduction of lead from gasoline between states (PDF) and the reduction of violent crime. She constructed a table linking crime rates in every state to childhood lead exposure in that state 20 or 30 years earlier. If lead poisoning is a factor in the development of criminal behavior, then countries that didn't switch to unleaded fuel until the 1980s, like Britain and Australia, should soon see a dip in crime as the last lead-damaged children outgrow their most violent years."
So does this mean with all the lead paint we are seeing in toys now, we will see another spike in violent behavior.
Interesting - but couldn't this be a correlation != causation issue? Also it seems to imply that violent or criminal behavior is due to organic brain damage. Is that a given?
Of course I haven't read the paper
...Freakonomics correlated the drop in crime rates with the legalization of abortion. Which sounds more sound of a theory to you?
Of course I haven't read the paper In another famous study, the decrease in number of pirates has been linked to global warming...
Bow-ties are cool.
... the crime wave will recede from Eastern US cities like Baltimore, where every single property in the entire city was painted with lead right up until the ban in 1978. Thing is, lead paint was used because of its durability, so there is no guarantee that these cities are even in the downward part of the curve yet, as the paint may just now be starting to chip and find its way into children's lungs/guts.
Levitt's book is cited in the first paragraph of the paper, which is very interesting, but rather hard to understand on a (very) brief reading. Essentially, she says that lead contributes 56% to the drop in crime, while the availability of abortions contributes 29%.
Reality is defined by the maddest person in the room
"It couldn't be related to the fact that we have more criminals than ever cooling their heels in prison?"
TFA says that _violent_ crime is down. If there are fewer violent offenders, then how does that explain why the prisons are overfilled? The prison population exploded because we're putting more _nonviolent_ offenders in jail.
Bad troll, no cookie. Try better next time.
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BMO
Personally, I think the most likely cause is one of:
* Reduction in the use of slide rules. With calculators it's easier to get a job as a clerk.
* Increase in CPU speed. Too much time playing games == less time being bad.
* Global warming. It's getting too hot to commit crime.
Engineering is the art of compromise.
Since 1992, approximately six million Americans have been arrested on marijuana charges, a greater number than the entire populations of Alaska, Delaware, the District of Columbia, Montana, North Dakota, South Dakota, Vermont and Wyoming combined. Annual marijuana arrests have more than doubled in that time.
Support NYCountryLawyer RIAA vs People
I can neither confirm nor deny that. But from what I do know, I say it's a very high probability that there at least is no lead added to new gasoline. When you add lead to gasoline, you are really adding tetraethylead (you can go to an automotive store and buy it). It does two important things 1) increases octane and 2) lubricates the fuel system. From what I know about cars, engines designed for unleaded gasoline are much different than leaded. Especially around the time of the switch over. For one, the compression of the engines is significantly different: Leaded gasoline engines were pushing 12:1 or 14:1 compression ratios, for unleaded, even today you don't see much above 9:1. So that means, at least there isn't enough lead in today's gasoline to increase the octane enough to have a high compression engine. Likewise, the valve seats and such are much different in unleaded engines because of the lack of lubricity in the fuel (and hence exhaust) now. I'd feel pretty confident saying that the amount of lean in fuel, if any, is orders of magnitude less than in leaded gasoline, and is negligible.
The book Freakanomics makes a good case for crime reduction based on the Roe v Wade - the legalization abortions. The logic goes that majority of kids who are not aborted end up being much more suspetible to crime. Another reason for reduced crime is increased police presence.
Roe v. Wade. Reduction in unwanted kids results in less criminals. More abortions for all!
- None can love freedom heartily, but good men; the rest love not freedom, but license. -- John Milton
The Scientific Method:
.... but that's the whole point. That's what makes this real science - somebody sticking his neck out in public, opening himself to the possibility of being wrong.
i) Observation
ii) Theory
iii) Prediction
iv) Experiment
In THAT order.
An awful lot of "science" these days seems to forget about the last two items - and they're the most important.
Will the prediction turn out to be true? Who knows
No sig today...
These statistical correlations are a complete crock. There are a million things that have changed over the last few years that could also be attributed.
One that was done piecemeal (so regression analysis could be performed) and which produced a strong signal under such analysis: Allowing law-abiding citizens to carry concealed weapons for self-protection against criminals. This drastically lowers the overall violent crime and injury/death rates (even if you DO count any crooks shot in self-defense as a "victim").
Interestingly, while many thought it might produce a short bloodbath (until criminals got the message that some of their victims might be armed), that didn't happen. Instead the violent crime rate just dropped, as criminals moved to less-armed areas, switched from muggings, armed robberies, carjackings, "hot" (occupied-dwelling) burglaries, to things like burglarizing UNoccupied homes and stores, or just found legal work. Rapes dropped like a rock, too (though they went up somewhat in nearby areas that hadn't yet liberalized their own laws.)
Turns out the crooks weren't SO stupid that they couldn't see the writing on that wall. And even those who didn't get the message right away usually weren't dumb enough to keep attacking, rather than run away, when they found themselves looking at the wrong end of a pistol.
(When Florida changed to non-discretionary CCW (i.e. the license has to be granted if the applicant jumps through the correct hoops and doesn't have a criminal record), one gang switched to hitting tourist in rental cars, on the assumption they'd be unarmed - both by airport regs and lack of a permit. Florida fixed that by removing the requirement that rental cars have distinctive markings/licenses and by issuing concealed carry permits to tourists. B-) Interestingly, even during the peak of the rob-the-Florida-tourists boom a tourist had less chance of being robbed in Florida than in California.)
Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
China is taking care of this problem with their usual efficiency, so stop giving them a hard time.
Re:Yet again it bears repeating...
Correlation does not imply causation. While the correlation may be very strong, causation cannot be assumed without ruling out many other potential contributing factors.
How many people have to post this needless gibberish over and over again? Is it some sort of karma whoring?
I mean, the effing SUMMARY got it 100% right:
"Even low levels of lead can cause brain damage, increasing the likelihood of behavioral and cognitive traits such as impulsivity, aggressiveness, and low IQ that are strongly linked with criminal behavior."
We know lead causes brain damage, and we know brain damage can lead to agressiveness, violence, etc.
"The NYTimes has a story on how the phasing out of leaded gasoline starting with the Clean Air Act in 1973 may have led to a 56% drop in violent crime in the US in the 1990s."
Key words: MAY HAVE LED TO. Its a hypothesis. Good.
They aren't asserting causation. They are noting a correlation, and using reasoning to form a hypothesis. So far so good.
An economics professor at Amherst College, Jessica Wolpaw Reyes, discovered the connection and wrote a paper comparing the reduction of lead from gasoline between states (PDF) and the reduction of violent crime. She constructed a table linking crime rates in every state to childhood lead exposure in that state 20 or 30 years earlier.
Documenting the correlation. Even better, its not anecdotal. We're collecting real empirical measurable evidence.
If lead poisoning is a factor in the development of criminal behavior, then countries that didn't switch to unleaded fuel until the 1980s, like Britain and Australia, should soon see a dip in crime as the last lead-damaged children outgrow their most violent years."
A useful prediction? Can it be? Holy shit. Its the full on scientfic method in action. Observe World, Formulate Hypothesis, Test Hypothesis.
I grant that is not the best possible test of the hypothesis, because its not a closed experiment, and its not really repeatable, and a lot of unknowns can get in the way, but we take what we can get. Human-centric sciences like medicine and psychology, or sciences like astrophysics or evolution don't have the luxury of perfect experiments - we can't raise humans in isolated bubbles, nor send a selection of stars into identicale blackholes nor watch a million isolated generations of people --
All we can do in these cases is come up with hypotheses and models, make predictions based on those models to see if we can find examples / counter examples in the observable world.
Overall, its good science here. If the dip in crime occurs where they occur when they predict it, it obviously it won't prove or disprove the hypothesis but it will add significantly to the body of evidence that supports it. If it doesn't occur then we'll have to refine or discard the hypothesis. If ultimately the hypothesis is junk it'll eventually get tossed out. Science is full of wrong hypothesises, but they are the best we have at any given time... that's how it works.
So what exactly do you object to here? That you felt the need to drone about the difference between causation and correlation. It seems everybody involved already got that memo.
In Soviet Russia, our new overlords are belong to all your base.
> Instead of really helping people, we as a society have just chosen to get rid of them before they become problems.
That was the original point. Don't believe me, go read the writings of Ms. Sanger, the founder of Planned Parenthood. She was pretty open about her notions of Eugenics and eliminating the unfit and the 'inferior breeds' from the genepool. Amazing that Jesse Jackson and AL Sharpton never have any problems with supporting politicians who support Planned Parenthood and abortion since such a high percentage of the aborted are 'their'[1] people and that this WAS (even if they won't say it in public anymore) the stated purpose behind the founding of the organization.
[1] According to both the 'Reverends' and the MSM they are the Official spokesmen for all people of African descent in the US, whether the actual people want them as their leaders or not.
Democrat delenda est
Reading the article, they already control for abortion, the average crime rate per year, the average crime rate for individual states, and even the effects of people moving from one state to another. The lead level measurements were finer grained than "lead existed before this date, then, everyone stopped using it"- they included state-by-state, year-by-year measurements in their lead data, adjusting for population density (as a surrogate for traffic density).
This was a sophisticated analysis; I wouldn't call it, as some commenters above have, "junk science". It would be surprising for their observed relation to hold, but their interpretation be incorrect. It would be interesting for someone to really come up with an alternative explanation of this paper's observations.
As a side note, I'm pretty sure that by now most lay people, and everyone reading this forum, is aware that correlation does not imply causation. And I'd be willing to guess that the vast majority of scientists have been aware of this elementary statistical fact for some time. It's likely that scientists take many potential influences into account before submitting for publication. So can we please exercise some restraint in the future and actually read the article before denouncing it as "junk science" because, as everyone knows, correlation is not causation? I am emphatically not asking people to take what the researcher says on faith, but if you decry the article without reading it, then your words are essentially noise.
There are techniques to take some account of these factors. According to the NYT article, the study's author "uses small variations in the lead content of gasoline from state to state to strengthen her argument." So we have: 1) a correlation between violent crime and presence of lead in the environment, 2) support from state-by-state comparisons, 3) lead poisoning is linked to brain damage resulting in violent behaviors. Is that enough? Probably not - but it's suggestive, and with such sensational claims I expect there will be plenty of peer review.
You're also accusing the result of being a "pet theory". It may be. It may be that many or most scientists cheat. But we shouldn't assume - with no evidence whatsoever - that any particular scientist is acting in bad faith. Do that, and we'll find scientists living down to our expectations.
You may find the study "hard to believe", that it could "prove anything you like". If you don't examine the method, your complaint could also be leveled at any study you like. If you want better science, make specific criticisms - unless of course you don't want science at all.
Lead levels in the Roman Empire would be worth a look.
They already were.
Body loads of lead were very high in the later periods - especially among the upper, decision-making, classes. To the point that lead was believed to have been the major cause of a lack of fertility among the upper classes and the decline of those families.
Turns out it wasn't the lead plumbing - where the lead pretty much stayed in the pipes. They had figured out that if you put a lead liner in wine bottles the wine stayed sweet as it aged, rather than turning sour. But that's not because it DOESN'T turn to vinegar - instead the vinegar (acetic acid) reacts with the lead to form lead acetate - which is so sweet it's also called "sugar of lead". And it's REALLY well absorbed by the body.
Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
"The American people overwhelmingly (not just a majority, but up to 80%) support marijuana criminalization."
From where do you get your stats, besides your arse?
"But more than legalization, I support democracy."
Then you should support the ability of states to decide on their own instead of the use of the commerce clause by the federal government to beat up states that don't toe the line, shouldn't you?
Funny about your use of the word "democracy" there when you actually support federalism. Troll much?
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BMO