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Yeah pretty sure that's because of other more obvious factors:

* Greater anonymity in cities * Higher population density * Juxtaposition of poverty and wealth




Are these factors so obvious?

As an example poverty is most prevalent in rural areas according to this study: https://www.google.dk/url?sa=t&rct=j&q=&esrc=s&source=web&cd...

Be careful of citing "obvious", it can be deceiving.

Note that I'm not arguing that lead in gasoline proves a definite link between crime in rural vs. urban areas, just noting that there is the same correlation as stated in the article. I merely thought it was interesting, and that it might be the same effect at work due to the dilution of lead in rural areas because there are fewer cars.


Juxtaposition of poverty and wealth, not poverty itself. In most American cities somebody from a poor neighborhood can walk a few blocks and mug a rich person at knifepoint, whereas in the average poor rural area, there aren't really any rich people around to rob.


That's true but the vast majority of urban crime is poor on poor and takes place in the neighborhood where the victim and perpetrator both live.


this is at best an anecdotal point, and seems more like something you just thought up. Is there any substance to this? Is crime in urban areas more prevalent because it is a shorter distance to walk for a potential mugger to get to a rich person he can mug?

This just doesn't seem very likely to me, but if you can back it up by numbers I'll gladly change my view.


> Is crime in urban areas more prevalent because it is a shorter distance to walk for a potential mugger to get to a rich person he can mug?

This is just a correlation, possibly meaningless, but an explanation for the decline in New York City crime over the last 30 years is that poor people can't afford to live there any more. It's just an opinion, true for most such views.

> ... but if you can back it up by numbers I'll gladly change my view.

Now that would be very difficult, even with the numbers. The number of poor people living in NYC is available, and the number of poor-on-rich crimes is available (both in sharp decline), but proving a connection between them is nigh impossible.


Why would that automatically lead to an increase in crime?

If you have wealthy areas, you have opportunities for less affluent people to get ahead through legitimate means. They have economic opportunities.

On the other hand an area that's entirely depressed is often infested with crime because there's no alternative to theft. The economic opportunities do not exist.


Higher population density seems obvious. Increasing density increases the opportunities for violence.

But, since violence is more often directed at people that are known, rather than strangers, I find the other two suspect.


You can be as sure as you like.

The fact remains that the concentration of lead in the living environment is the most strongly correlated measurable datum to crime rate than any other single factor.

If you compare factors directly relating to motives, methods, and opportunities (the crime triangle) in different cities, the correlations are still weaker than whether the population was exposed to lead pollution as children.

This is not the first article on this topic that has been published. None of them, as far as I am aware, have proven causation rather than correlation--probably because proving it would take 20+ years and be grossly unethical.

But nevertheless, it would be interesting to see what happens if one city decided to completely eradicate lead contamination from within its limits, and compare it against cities of similar character that chose not to do so over the next 30 years.


Not disagreeing outright, but there are studies[1] that link high-poverty areas with higher lead concentrations. There was also an interactive map, some time ago, that showed lead soil levels by zip code and they definitely seemed to match up with more problematic neighborhoods. Clearly, the factors you call out have an influence, but lead seems to be a part of that equation.

[1]: http://www.ncbi.nlm.nih.gov/pubmed/22752852

Edit: switched low with high.


(you mean high poverty areas correlated with lead concentration, right?)

My first guess would not be that lead causes poverty (is that what you are suggesting?), but that lead-producing activities (highways, factories, waste dumps) tend to be undesirable, and tend to be placed in poorer neighborhoods because poor people have less political power.


Yes, I do mean areas with high poverty areas or low income.

I am not really suggesting any particular cause of poverty, but lead-soil levels seem to have some negative effect. The more important suggestion is that its not just income disparity, anonymity and juxtaposition of poverty and wealth, if at all, that leads to higher crime rates in cities.

In fact, mixed-income neighborhoods have been linked to better social mobility, but that is getting off-topic.


I guess it's topical if it's about proper conclusions from statistics.

I think your conclusion, from correlation between lead concentration in soils to conclusiong "lead-soil levels seem to have some negative effect" -- is entirely unjustified.

The alternate hypothesis I mentioned seems as, or more, plasuble. That it's not lead-soil levels that are having any effect at all, but rather that lead-producing activities are socially undesirable, and end up in poor neighborhoods because poor people lack political power.

I suppose the scientific method would be to devise an experiment or investigation that would attempt to distinguish between these two hypothesis. Possibly people already have, and arguing about it in the academic literature now.

One danger of concluding causation from correlation in the 'big data' era is how easy it is to go hunting for correlations. If I test ketchup consumption against 1000 other variables, it may be fairly likely that I'll find a correlation against at least one of them. (If I flip a coin 10 times; and then do this experiment 1000 times, it's not unlikely that at least one of those 10-times iterations I'll get 10 ten heads). So maybe I find that ketchup consumption is very closely correlated with public transit availability, across cultures and times and governments. That doesn't really mean that ketchup causes public transit or vice versa, it just means that if you have enough data, you're going to find happenstance correlations.


It seems you are trying hard to find something in my statement with which to refute. I was merely pointing out that the GP's conclusions are probably incomplete, given the data we have on lead.

Most of my previous comments were quite non-committal. For instance, the phrase "lead-soil levels seem to have some negative effect" was cherry-picked for your analysis, and given much stronger meaning than intended. First, let's examine the word choice of "seem". It means "give the impression or sensation of being something or having a particular quality." This modifies the statement, to imply that the data "gives the impression" that there is "some negative effect". This is a much weaker statement than a hypothesis on the effect of lead-soil levels on poverty-stricken neighborhood. Perhaps, that statement would have been more clear if written as, "lead-soil levels seem to have an effect on crime". The implication from the sentence that follows is that the value of "some" is "crime".

It very well could be that lack of political power caused lead-producing activities to be concentrated in low-income neighborhoods. However, the issue at hand is not that lead-soil levels cause poverty; it's that lead-soil levels increase the incidence of crime. This point may not have been clear, as conceded above.

Indeed, correlation does not imply causation, but we know much about the health effects of lead [1] and its impact on decision making. We know that the correlation of crime rates with increasing and decreasing lead-levels, in a variety of situations, throughout many policies and governments, holds. We know both a pathway and have a strong correlation. Dismissing this as happenstance is unwise.

[1]: http://en.wikipedia.org/wiki/Lead#Health_effects


Those seem to absolutely be factors, perhaps the overwhelmingly influential ones, but the question is how influential is this leaded gas business. Where does it fit into the big picture?


All of those factors have increased in the past twenty years and yet crime continues to fall. Your explanatory paradigm needs reworking.


Yeah I'm pretty sure I'm gonna give more credence to scientific studies than Timmmmmm's opinion on what is obviouis.




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