Correlation, causation, and big changes

Scott Alexander recently argued that building more housing in a given city causes housing prices to go up in that city. He acknowledged that previous studies had found the opposite relationship, but suggested that he was more impressed by the strong positive correlation between population and prices when there are big changes: Matt Yglesias tries […]
Correlation and causation – Econlib

The Economist has an interesting article on obesity. You may know that in earlier centuries the rich tended to be more obese, whereas today the correlation has flipped in many developed countries. What you may not know is that this new correlation is almost entirely driven by women: That poor people are more likely to […]