More on Glaeser and Houston

From the comment section to my recent post on Edward Glaeser (from a reader who was NOT happy with my piece), here's a quote from Glaeser that does put Houston where it belongs:

If our Houston family's income is lower, however, its housing costs are much lower. In 2006, residents of Harris County, the 4-million-person area that includes Houston, told the census that the average owner-occupied housing unit was worth $126,000. Residents valued about 80% of the homes in the county at less than $200,000. The National Association of Realtors gives $150,000 as the median price of recent Houston home sales; though NAR figures don't always accurately reflect average home prices, they do capture the prices of newer, often higher-quality, housing.

Just to review, I had criticized Glaeser for this quote:

Why is housing supply so generous in Georgia and Texas? It isn’t land. Harris County, Tex., which surrounds Houston, has a higher population density than Westchester County, N.Y.

So should we write off the "surrounds" as a bad choice of words and move on to another topic? Not quite yet. The trouble is that the placement of Houston doesn't just shift; it shifts in a way that's necessary for Glaeser's argument to work. If Houston weren't in Harris then the Westchester comparison would make sense. Here are the population densities (all numbers courtesy of Wikipedia)

Harris             2,367/sq mi
Westchester    2,193/sq mi

But Harris does include Houston. None of the counties that contain parts of NYC have a density lower than Harris (not even close). Of course, the county to county comparisons are problematic, but we get the same results from the much cleaner city-to-city comparison.

Houston              3,623/sq mi
New York City   27,012.5/sq mi

We could go back and forth on the best way to slice this data, but this is a big difference to get around. This doesn't mean that population density is driving the difference in housing between New York and Houston or regulation isn't the main driver here.

But the Harris/Westchester example Glaeser used to prove his point was badly chosen and it's worrisome that neither he, the New York Times or the vast majority of the blogosphere picked up on that.