Great piece of research out of GWU on walkability of cities. I particularly find interesting the correlation between higher walkability and higher GDP. In many ways it makes sense, but also wonder if it’s not just a product of overall density first (i.e. density is caused by lots of people/businesses being close together – thus higher GDP), and as a result these are more walkable cities. I recognize the fallacy in my point, in such that two dense areas are not the same from the stand point of walkability.