3 ms·

> This suggests either that the negative results were truncated out, negative results have been hacked to positive ones, or there is some confounding factor at

> This suggests either that the negative results were truncated out, negative results have been hacked to positive ones, or there is some confounding factor at play. Here's a potential confounding factor: maybe the cluster of very weak positive effects includes some studies that initially showed very weak negative effects but that had their methodology tweaked to avoid showing an "impossible" result. (I don't think anyone argues that atmospheric lead _decreases_ crime rates.) If so, that would mean that there are some "missing" negative studies, but that there are also "too many" zero/very low result studies. If corrected for that, I suspect that the meta-analysis would show a positive effect size, though lower than 0.33.

jsnell 5y ago
That's the "negative effects hacked to positive ones" explanation.
geeB 5y ago
> I don't think anyone argues that atmospheric lead _decreases_ crime rates. Although in principle I don't see why it couldn't be the case, as leas poisoning also has symptoms such as depression and fatigue, which could marginally sway people towards inaction.
- pmoriarty 5y ago
  "lead poisoning also has symptoms such as depression and fatigue, which could marginally sway people towards inaction." That could be counteracted by stimulant use, for example.
  - burnished 5y ago
    What is the point you are trying to make? I don't quite see how your comment fits into the overall topic, re: lead based crime.
    - pmoriarty 5y ago
      Let me spell it out: If it's true that lead exposure motivates crime, but at the same time causes people to feel too depressed and fatigued to act on their motivation, then my point is that if lead-exposed people then take stimulants (like meth, coke, or crack, for example) then those stimulants could counteract the depression and fatigue effects of the lead enough to allow people to act on their motivation to commit crime. In case some of the downvoters are skeptical that stimulants could counteract depression or fatigue -- they certainly can. Not saying this is a smart thing to do, due to the addictive potential of these substances or their other deleterious effects. But they certainly can stimulate people in to action if they're otherwise too depressed or tired to do anything. This is just a hypothesis. But it would be interesting to see if there's a correspondence between lead exposure, stimulant use, and crime. The nexus of lead exposure, alcohol, and crime would also be interesting to investigate, as alcohol is already well known to be associated with violence, impulsive behavior, and poor decision making -- adding lead exposure in to the mix might potentiate this in to criminal activity.
      - Dylan16807 5y ago
        We already have a strong list of ways lead poisoning can increase crime. When someone is brainstorming to try to find some possible way it could possibly decrease crime, you don't need to point out more ways those reasons could cause increases.
        pmoriarty 5y ago
        What? I was responding to someone who said "lead poisoning also has symptoms such as depression and fatigue, which could marginally sway people towards inaction." What I just quoted is an argument against lead being implicated in an increase in crime. I was just pointing out why lead might be implicated in crime after all, despite the above quoted argument against it. So what exactly am I doing wrong here?
        Dylan16807 5y ago
        Because they already know there are lots of arguments for lead to cause an increase. The part you quoted was them reaching on purpose to come up with an argument that could even possibly go the other way. They already know it's likely wrong. You pointing out it could be wrong isn't needed. They already know there are lots of anti-lead arguments, so you making another one isn't needed.
yxhuvud 5y ago
> I don't think anyone argues that atmospheric lead _decreases_ crime rates. Scientists wouldn't have to argue this. They could just argue the null hypothesis as the results were really close to 0.

jsnell 5y ago

That's the "negative effects hacked to positive ones" explanation.

geeB 5y ago

> I don't think anyone argues that atmospheric lead _decreases_ crime rates. Although in principle I don't see why it couldn't be the case, as leas poisoning also has symptoms such as depression and fatigue, which could marginally sway people towards inaction.

pmoriarty 5y ago
"lead poisoning also has symptoms such as depression and fatigue, which could marginally sway people towards inaction." That could be counteracted by stimulant use, for example.
- burnished 5y ago
  What is the point you are trying to make? I don't quite see how your comment fits into the overall topic, re: lead based crime.
  - pmoriarty 5y ago
    Let me spell it out: If it's true that lead exposure motivates crime, but at the same time causes people to feel too depressed and fatigued to act on their motivation, then my point is that if lead-exposed people then take stimulants (like meth, coke, or crack, for example) then those stimulants could counteract the depression and fatigue effects of the lead enough to allow people to act on their motivation to commit crime. In case some of the downvoters are skeptical that stimulants could counteract depression or fatigue -- they certainly can. Not saying this is a smart thing to do, due to the addictive potential of these substances or their other deleterious effects. But they certainly can stimulate people in to action if they're otherwise too depressed or tired to do anything. This is just a hypothesis. But it would be interesting to see if there's a correspondence between lead exposure, stimulant use, and crime. The nexus of lead exposure, alcohol, and crime would also be interesting to investigate, as alcohol is already well known to be associated with violence, impulsive behavior, and poor decision making -- adding lead exposure in to the mix might potentiate this in to criminal activity.
    - Dylan16807 5y ago
      We already have a strong list of ways lead poisoning can increase crime. When someone is brainstorming to try to find some possible way it could possibly decrease crime, you don't need to point out more ways those reasons could cause increases.
      - pmoriarty 5y ago
        What? I was responding to someone who said "lead poisoning also has symptoms such as depression and fatigue, which could marginally sway people towards inaction." What I just quoted is an argument against lead being implicated in an increase in crime. I was just pointing out why lead might be implicated in crime after all, despite the above quoted argument against it. So what exactly am I doing wrong here?
        Dylan16807 5y ago
        Because they already know there are lots of arguments for lead to cause an increase. The part you quoted was them reaching on purpose to come up with an argument that could even possibly go the other way. They already know it's likely wrong. You pointing out it could be wrong isn't needed. They already know there are lots of anti-lead arguments, so you making another one isn't needed.

yxhuvud 5y ago

> I don't think anyone argues that atmospheric lead _decreases_ crime rates. Scientists wouldn't have to argue this. They could just argue the null hypothesis as the results were really close to 0.