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America's Real Criminal Element: Lead

motherjones.com

11–20 of 201 posts

Re: America's Real Criminal Element: Lead

#12

I'm tempted to repeat the oft said correlation is not causation. But really I have never thought that captures the problem I have with studies like this. Of course correlation does not necessarily imply causation. What I really find to be problematic is a small time series of data of a facet of a human behaviour across a population is probably going to correlate extremely well to many other time series across the sam…

This article cites research that goes way beyond the usual sort of correlation. How much stronger would the evidence need to get?

Re: America's Real Criminal Element: Lead

#13
post #5
post #4

Fun fact: the banning of leaded gasoline was one of the biggest regulatory successes in history, and went a long way to validate the model. The use of leaded gasoline was a classic market failure. It saved a small number of companies a relatively small amount of money, but was on the net a huge negative for the overall economic because it basically pumped lead directly into the bloodstream of children through their l…

Your profile says you're a lawyer. I have a question for you. Why did they need to ban leaded gasoline specifically? Wasn't it already illegal for anyone to spread poison in the air? Why was new regulation needed? Or, by "regulatory success", do you simply mean the recognition by the government that lead is poisonous?

The driving factor was clean air legislation generally, which mandated the use of catalytic converters in new cars. Lead poisons the catalyst; a tank of leaded gasoline would be plenty to render a catalytic converter useless.

Eliminating atmospheric lead may have been a consideration, but in my recollection it wasn't the primary consideration; people were more concerned about unburned hydrocarbons producing smog.

Re: America's Real Criminal Element: Lead

#14

I view the drop in crime as the result of a perfect storm of many factors, and perhaps this is another one. The explosion of media and the Internet occurred around the same time, so it's hard to say what caused it.

I think that's where "they" would point to the "distribution" evidence, that shows varying rates of the same correlation geographically.

If we go on that, then you'd have to find another event that occurred at similar rates in similar geographic areas.

Now, if only there were medical indications that lead causes violent behavior... the article only points to IQ issues, though there is likely more evidence elsewhere.

Re: America's Real Criminal Element: Lead

#17
post #12

I'm tempted to repeat the oft said correlation is not causation. But really I have never thought that captures the problem I have with studies like this. Of course correlation does not necessarily imply causation. What I really find to be problematic is a small time series of data of a facet of a human behaviour across a population is probably going to correlate extremely well to many other time series across the sam…

This article cites research that goes way beyond the usual sort of correlation. How much stronger would the evidence need to get?

I'm not sure, how strong should such a correlation be to be considered evidence? That's the real question. And I think when it comes to annual averages of broad trends its a real question how we should interpret correlations. To me this article is data porn, its a story with data. It may be some part of the truth, but I think it exists to entertain the data literate - so we can follow along with the numbers and pat ourselves on the back for a fact discovered. Its enough analysis to be dangerous.

And in case hackernews has become so infected with the kind of reddit thinking that can only see in black and white - yes I think reducing lead in gasoline is a very good thing.

Re: America's Real Criminal Element: Lead

#18
post #4

Fun fact: the banning of leaded gasoline was one of the biggest regulatory successes in history, and went a long way to validate the model. The use of leaded gasoline was a classic market failure. It saved a small number of companies a relatively small amount of money, but was on the net a huge negative for the overall economic because it basically pumped lead directly into the bloodstream of children through their l…

Along with the environment, what other aspects of our world are fundamentally socialized? I'm thinking things like risk of asteroid impact.

Re: America's Real Criminal Element: Lead

#19
post #9
post #5

Earlier quoted context omitted.

Your profile says you're a lawyer. I have a question for you. Why did they need to ban leaded gasoline specifically? Wasn't it already illegal for anyone to spread poison in the air? Why was new regulation needed? Or, by "regulatory success", do you simply mean the recognition by the government that lead is poisonous?

It's not illegal to spread poison in the air. Every time you drive your car you're spreading harmful chemicals into the air. Every factory or industrial operation spreads harmful chemicals into the air and water. You could theoretically ban pollution. That actually used to be the law in the 1600's. E.g. if you owned land on a river, the water had to leave your property as clean as it came in. As the industrial revolu…

Very informative, thanks.

Re: America's Real Criminal Element: Lead

#20
post #12

Earlier quoted context omitted.

This article cites research that goes way beyond the usual sort of correlation. How much stronger would the evidence need to get?

I'm not sure, how strong should such a correlation be to be considered evidence? That's the real question. And I think when it comes to annual averages of broad trends its a real question how we should interpret correlations. To me this article is data porn, its a story with data. It may be some part of the truth, but I think it exists to entertain the data literate - so we can follow along with the numbers and pat o…

The strength of the correlation or its time-scale have no bearing on whether the correlation should be considered evidence of causation. The fatal flaw of a correlation is that it can be specious — it can appear to explain reality, but really there's a third variable responsible for driving the phenomenon you're interested in.

In this case, lead exposure and crime rate are correlated, but maybe lead doesn't cause crime at all: maybe something else causes crime that also happens to correlate with lead exposure. Who knows, maybe a certain pesticide was used at the same time that lead gasoline came into vogue, and that's really the true cause of the rise in crime rates.

In research like this, when you can't do a manually controlled experiment, you have to control for hidden variables by some other means. And that's precisely what the investigators in this article did: they varied the input data to try to "shake out" other variables that might be behind the correlation. They looked at different time scales, different geographies, and different demographics, in an attempt to control for hidden variables that might be related to any one of those things. Every time you vary the input data and keep finding a correlation, your evidence of a causative relationship goes up.

The gold standard, of course, would be to expose two random, double-blind sets of infants to lead and to a control substance and see what happens. But since that would be unethical (as we have reason to think lead is bad for you), we're stuck with animal studies or retrospective studies. Personally, I find the evidence in this article impressive, but it would take quite a lot of looking into their specific methods to come to any real conclusion.

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