Left-NIMBYs Take Another Loss - And This One Is Really Embarrassing

The Urban Institute Study Loved By Supply Skeptics Goes Up In Flames

Firefighters in full gear spray water on a flaming dumpster during a training exercise outside, with a building and metal stairs in the background.

As I wrote last year, the Urban Institute produced a study purporting to show that land use reforms did not substantially increase housing production. I noted that the study has become very influential, particularly among Left-NIMBYs, who want to maintain strict land use controls but not acknowledge that such controls make housing more expensive (which obviously impacts low- and middle-income people the most). If you don’t like the term “Left-NIMBYs,” then use “supply skeptics”: they reject the notion that allowing more housing construction will stabilize prices.

I expressed a lot of my own skepticism about this study, mainly because of the data quality issues. The study purports to show that jurisdictions that have enacted “land use reforms” have built virtually no new housing over the baseline – only 0.8% more. The problem is that “land use reforms” can mean about a million different things, so the number really means very little.

Well, others have looked more closely at the study, and as it turns out, that was the least of its problems. The Urban Institute study used an innovative method to figure out whether jurisdictions had enacted land use reforms: an AI tool trawling through newspapers for references to them. But then the center-right American Enterprise Institute looked more carefully at those data points. And it found something very very ugly:

Our independent review reveals that 60 of these articles should be disqualified outright due to duplication, incorrect geographic attribution, or policies that only affected commercial or industrial areas or properties. Among the remaining 120 entries, 118 are either incorrectly classified in direction (more vs. less restrictive), are either not major municipality-wide reforms, or have insufficient information to accurately determine policy direction. After a thorough and painstaking review of all 180 cases, we found only two that plausibly qualify as “major” reforms—and even these warrant caution given uncertainty about whether their supply impact was measurable using Stacy et al.’s methodology.

No less than a fifth of the 180 land use changes were “attributed to the wrong city.” For example, the Urban Institute researchers said that a height limit increase in Aventura, Florida had actually taken effect in Miami. Why? Because the article about this increase appeared in the Miami Herald. (The article’s lead sentence is: “Developers who had plans to build in Aventura on hold can now proceed, but face stricter zoning laws.”).

Put another way, this very-cited study is a hot flaming piece of garbage.

When I was in practice, a senior attorney told me: “Do the easy things right.” Proofreading (even with spellcheck), being on time, etc. etc. Well, here’s another one: check the computer’s work. It was obvious even last year that there were significant problems with relying on AI, and these guys didn’t bother to do it. In a reply to the AEL critique, the Urban Institute researchers say that they had human beings check the results. That makes it even worse!

Resnikoff thinks that they were so convinced that their program was right, they didn’t check. The cynic in me suggests that maybe it’s that they got great results and didn’t really want to find out if they were right. And now they have egg on their face.

Or maybe not. AEI of course covered their own study. Resnikoff wrote about it. But at least a Google search does not reveal any press coverage about such a spectacular failure – and importantly, one that has dominated Left-NIMBYist discourse. Perhaps this flameout will just mean that people won’t cite it anymore.

But maybe not. Scholars and popular writers routinely cite books that have been comprehensively debunked because they tell the story that the scholars and writers want to tell. Attempts to set the record straight (as I have tried to do in areas like water policy and fair housing) get the worst academic treatment: they are not attacked, but simply ignored.

I wonder if the same thing will happen here. Lots of people want to tell the supply skepticism story. So it will be told.

2 Replies to “Left-NIMBYs Take Another Loss — And This One Is Really Embarrassing”

This is purely anecdotal, but housing prices haven’t come down in Minneapolis and St. Paul after zoning was relaxed to allow more density in what were previously single-family residential zones. So much goes into this. Land prices are higher in the core cities in most suburbs, including those at the exurban fringe and in aging inner-ring and even mid-tier suburbs. Suitable building sites are scarcer in the core cities. Building codes are stricter, and more strictly enforced. Multiple dwellings more often use costlier union labor in the cities. There’s also a widespread cultural bias and consumer preference in favor of the proverbial single-family home with a 2-car garage and a yard for the kids to play in, limiting consumer demand for multiple dwellings except at both ends of the income scale. The poor often have limited choices; it’s either a low-rent apartment where it’s hard for the developer and landlord to tutn a profit, or lower-cost housing like a trailer or a modest single-family home at the urban fringe. At the other end of the scale, some high-incone, high net worth people, e.g., empty nesters, prefer the convenience and urban amenities associated with high density, high-rent living. Relaxed zoning may marginally bring down these high-end rents or condo costs, but it won’t do much for the poor or the middle class still chasing that “American dream” of a single-family home in a safe neighborhood with good public schools. Where zoning codes are strictest here in the Twin Cities metro is not the core cities but a handful of high-end suburbs where “snob zoning” prevails. The core cities make room for all housing types. For the many who don’t want density snd urban life, there’s still plenty of room at the urban fringe. I suspect this is true of many, if not most, U.S. metro areas. Cities on both coasts are certainly different, but they may be the exception, not the rule.

I have a subject to propose for study. As a result of the California Democratic Party’s total capitulation to Big Real Estate, are cities now building more at their edges? Let’s call it Screw Your Neighbor planning.

Because I seem to be seeing it happen.

But you-all here probably don’t care. I’ve never heard of that study and I am not in the least embarrassed.

And please – “stabilize” pricing?

Nice try. You get a cigar just for trying.