Do you not admit the confounder that proximity to a lead factory should also correlate with socioeconomic status?
I don't have time to check out the article this week, but will soon.
I don't have time to check out the article this week, but will soon.
An important concern in a cross-sectional study such as ours is that the cities that installed lead pipes in the nineteenth century might have differed from the cities that did not in unobserved ways that were correlated with their homicide rates. Based on available data on the characteristics of the cities in our sample, we find little evidence that the cities that used lead pipes differed in observable ways from the cities that did not. Although larger cities, denser cities, and cities with comparatively low rates of home ownership were more likely to have used lead pipes, so were better-educated cities. High-homicide southern cities, meanwhile, were less likely to have used lead pipes. When we predict whether cities used lead pipes using all covariates, the only difference that remains statistically significant is the city population.
Using the Integrated Public Use Microdata Series (IPUMS) sample of the 1900 census, we calculate several city-level covariates that could be correlated with both lead pipe use and crime.17 These include each city’s population, population density, home ownership rate, and literacy rate, the share of each city’s population composed of African Americans, foreign-born residents, and single men aged 18 to 40, and the share of each city’s employed population working in manufacturing. We also create covariates for cities’ latitude and longitude...
> I don't have time to check out the article this week, but will soon.
Maybe reading first before accusing them of bad science is a good idea?
Paper's here: http://scholar.harvard.edu/files/jfeigenbaum/files/feigenbau...
The real kicker is that lead pipes combined with acidic water have a higher effect than lead pipes combined with basic water.