Lead and Crime: Another Look | Hacker News Reader

Lead and Crime: Another Look

motherjones.com

42 pointscurtis11 comments

I'm not surprised. Any time I see a research paper that suggests a highly complex issue, like crime, can be neatly explained by a single variable, my BS meter goes off.

Could a reduction in lead levels contribute to the drop in crime? Sure, but any effect would likely be drowned out by the multitude of other changes that have happened over the past 60+ years.

I'm not sure what it is, but humans seem to be highly suceptable to simple explanations for the world. If you need some examples, just browse snopes.com

>I'm not sure what it is, but humans seem to be highly suceptable to simple explanations for the world.

Most things really are simple; If you see smoke, the simplest explanation happens to be correct: there's fire.

The bias towards simplicity can also be seen as a bias towards parsimony, which is almost always a good thing. We don't immediately recognize this truth because we don't conjure up trivial examples, even though the overwhelming majority of our reasoning is spent on trivial phenomena.

Also he's disputing a straw man. No one has claimed that all crime can be explained by a single variable. Only that a variable can have a big effect. Other "simple explanations" for crime could be poverty, broken homes, education, all the traditional explanations. All those are simple explanations and single variables.

I understood his claim a bit differently, namely as "Lead is an epiphenomenon, and a single variable with a big effect is likely to be an epiphenomenon".

To be sure, I think the logic goes like this:

- Lead is positively correlated with crime

- Reduction in lead-levels is associated with multiple factors that are in turn associated with gentrification

- Thus, these gentrification factors are the true cause, and lead-levels just happen to correlate with them.

Same with the abortion thing. The problem with complex causality is there's arrows going everywhere.

What's interesting to me is less the question of violent crime trending with lead exposure (or abortion), but more the holistic view of society getting more liberal.

As violent crime goes down, as dangerous chemicals/metals are removed from the environment, as the economy improves: all of these have an effect on the other (and I'm sure there are more). Clearly it would be difficult to create a study across all of those cohorts, but the point is that everything is improving, and with it the tendency for our society to be more accepting of differences.

"Can it really be true that violent crime was declining between 1973-91? There's no question that this is what the NCVS data tells us, but it sure doesn't match what everyone thought was going on at the time. By the early 90s, virtually everyone in America was convinced that (a) crime had been rising relentlessly for decades and (b) it would continue rising. (Remember "superpredators"?) At a purely gut level, a crime decline during this period sure doesn't feel right."

I think this can and may be true. See Pinker's arguments in The Better Angels of our Nature. It seems obvious to me that people's perceptions of crime are influenced to a huge extent by media reporting. People have irrational, unfounded beliefs all the time, so I don't see why they should be indicative of anything.

For all the faults of the reporting of crimes, the assumptions being made are not nearly as logically sound as the assumptions seem to assert. Exposure to leaded gas affects brain development, and impulse control. Alcohol for me also affect my impulse control, and I become more aggressive, and in my youth, violent/destructive. But at no point is my moral centre so far off that murder becomes a viable option. So the assumption that violent crime rates matches murder rates proportionally, is throwing another unknown variable into the mix, and attempting to make that appear far more rational than it it.

I think most murders are just spur of the moment assaults that go too far, the person dying is not premeditated like an Agatha Christie novel.

Reminds me of http://www.tylervigen.com/spurious-correlations

I don't think this is a spurious correlation, so much as an epiphenomenon.

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