4 ms·

I'll echo bckygldstn's criticisms[1] and add a few of my own. The "lead-crime hypothesis" is a very obvious example of correlation not implying causation. For

I'll echo bckygldstn's criticisms[1] and add a few of my own. The "lead-crime hypothesis" is a very obvious example of correlation not implying causation. For example, rock music causes crime. Rock music grew in popularity in the late 50's and early 60's, peaked between the late 60's and early 90's, and declined thereafter. Just like crime! In fact, the harder they rocked the worse the crime rate got. I guess Tipper Gore was right all along. Rock music causes crime. Margarine causes crime. Johnny Carson causes crime. The Boston Celtics cause crime. The Japanese economy, big hair, VHF television, polyester, yearly Oldsmobile sales: all cause crime. During the period leaded gasoline was sold, Canada allowed 0.77 grams of lead per liter of gasoline, nearly three times the US limit of 0.29 g/l.[2] Yet the crime rate in Canada was (and continues to be) far lower than in the US.[3] In Mexico, leaded gas remained commonplace much later than it did in the US, and yet crime fell dramatically during the period leaded gas was sold, and increased dramatically after it stopped being sold.[4] One thing we could look at is people who had the highest lead exposure. Lead miners, paint factory workers, house painters, fuel refinery workers, gas station attendants, auto mechanics, etc. I would confidently bet the farm that, adjusting for sex and income, there was no statistically-significant correlation between these professions and crime. Aviation gasoline, as used in small propeller planes, still contains lead. We could also look at present-day flight instructors, airplane mechanics and people who live near general aviation airports. I would likewise expect there to be no relationship. Here's something that's known to cause crime: young men. The Baby Boomers were the largest generation ever, which means between the late 60's (oldest Boomers entering their late teens) and early 90's (youngest Boomers entering their 30's), there was a particularly large population of young men. This doesn't explain the entire rise and decline in crime (the Boomers weren't that much larger than other generations), but it's a better starting place than lead paint. [1] https://news.ycombinator.com/item?id=16025762 https://news.ycombinator.com/item?id=16025762 [2] http://www.columbia.edu/itc/sipa/envp/louchouarn/courses/env-chem/Pb-Rise&Fall(Nriagu1990).pdf http://www.columbia.edu/itc/sipa/envp/louchouarn/courses/env... [3] https://ourworldindata.org/wp-content/uploads/2013/03/homicide-rates-in-the-united-states-1950-2010-and-canada-1961-2009-pinker-2011-jpg.jpg https://ourworldindata.org/wp-content/uploads/2013/03/homici... [4] http://www.slate.com/content/dam/slate/articles/news_and_politics/foreigners/2014/12/141209_Charts-Homicide-Rates-Mex.jpg.CROP.promovar-mediumlarge.jpg http://www.slate.com/content/dam/slate/articles/news_and_pol...

taeric 9y ago
I like the data on gas, though I'm not as sold that you have successfully ruled out lead paint. I'm also not sure on your argument for how "young men" cause crime. Where are you wanting to start, exactly? Do we have numbers that show a higher population of males in the US than in Canada over that time period?
- smitherfield 9y ago
  >I'm also not sure on your argument for how "young men" cause crime. Criminals skew young and overwhelmingly male.[1] >Do we have numbers that show a higher population of males in the US than in Canada over that time period? It appears the baby boom was about the same size or slightly larger in Canada than the US.[2] As you can see from my first post, there also was an increase in crime in Canada during the same time period as in the US, but not as pronounced. Unlike Corn, who is claiming that leaded gasoline is the primary cause of crime, such that it explains the entire or nearly the entire late 20th-century rise and fall in the US crime rate, I am making the much more conservative claim that the ratio of young men in a population is a cause of crime. Indeed, as I said, the Baby Boom was not large enough for it to have been the primary cause of the US crime wave. (Although it might be sufficient to explain the relatively-smaller Canadian crime wave over the same period). [1] https://i.imgur.com/2WscI1P.jpg https://i.imgur.com/2WscI1P.jpg — The chart understates the correlation between youth and crime, because prisoners might be serving multi-year sentences, they may have got away with other crimes prior to those they're serving time for, and first-time offenders are more likely to receive a shorter or no prison sentence than recidivists are. [2] https://imgur.com/a/NFLfm https://imgur.com/a/NFLfm
  - taeric 9y ago
    Ah, I have not fully read this person's claim that lead is the cause for crime. I have taken a personal liking to the theory, since it at least has some causal capabilities to it. (Specifically, we know it directly has an effect on brain chemistry.) So, to that end, I am probably arguing a different take. Even if I expect it to be a majority parameter, I would also expect at a local level there will be major variance in how influential it is. I'm still not sure how your argument is working, though. The size of the baby boom would be mostly irrelevant, at a major numbers position. Unless you are arguing there is a saturation point for how many males a population can sustain, not a percentage that it can sustain. (You specifically claim ratio, though.) Which is not to say I am trying to shoot it down. I'm very interested in exploring the question. My strongest suspicion is that there is something else we were putting people in contact with. Would be amusing if it was DDT levels or some such that we know is bad for other reasons and stopped completely. That said, I fully acknowledge this as a bias of mine. That I suspect it is not the direct things people think they did that caused something to improve, but something else that happened to happen at the same time. Lead is attractive because we know it is terrible for you.

taeric 9y ago

I like the data on gas, though I'm not as sold that you have successfully ruled out lead paint. I'm also not sure on your argument for how "young men" cause crime. Where are you wanting to start, exactly? Do we have numbers that show a higher population of males in the US than in Canada over that time period?

smitherfield 9y ago
>I'm also not sure on your argument for how "young men" cause crime. Criminals skew young and overwhelmingly male.[1] >Do we have numbers that show a higher population of males in the US than in Canada over that time period? It appears the baby boom was about the same size or slightly larger in Canada than the US.[2] As you can see from my first post, there also was an increase in crime in Canada during the same time period as in the US, but not as pronounced. Unlike Corn, who is claiming that leaded gasoline is the primary cause of crime, such that it explains the entire or nearly the entire late 20th-century rise and fall in the US crime rate, I am making the much more conservative claim that the ratio of young men in a population is a cause of crime. Indeed, as I said, the Baby Boom was not large enough for it to have been the primary cause of the US crime wave. (Although it might be sufficient to explain the relatively-smaller Canadian crime wave over the same period). [1] https://i.imgur.com/2WscI1P.jpg https://i.imgur.com/2WscI1P.jpg — The chart understates the correlation between youth and crime, because prisoners might be serving multi-year sentences, they may have got away with other crimes prior to those they're serving time for, and first-time offenders are more likely to receive a shorter or no prison sentence than recidivists are. [2] https://imgur.com/a/NFLfm https://imgur.com/a/NFLfm
- taeric 9y ago
  Ah, I have not fully read this person's claim that lead is the cause for crime. I have taken a personal liking to the theory, since it at least has some causal capabilities to it. (Specifically, we know it directly has an effect on brain chemistry.) So, to that end, I am probably arguing a different take. Even if I expect it to be a majority parameter, I would also expect at a local level there will be major variance in how influential it is. I'm still not sure how your argument is working, though. The size of the baby boom would be mostly irrelevant, at a major numbers position. Unless you are arguing there is a saturation point for how many males a population can sustain, not a percentage that it can sustain. (You specifically claim ratio, though.) Which is not to say I am trying to shoot it down. I'm very interested in exploring the question. My strongest suspicion is that there is something else we were putting people in contact with. Would be amusing if it was DDT levels or some such that we know is bad for other reasons and stopped completely. That said, I fully acknowledge this as a bias of mine. That I suspect it is not the direct things people think they did that caused something to improve, but something else that happened to happen at the same time. Lead is attractive because we know it is terrible for you.