[hnboredhn]

Isn't the obvious arrow here that high prices drives density? The fact that NYC is the densest and most expensive seems to be an obvious story of high prices incentivizing people to build up.

The question is whether or not an old building being replaced by a tower or a single family house will lead to more expensive housing throughout the city. I still am confused as to how density would hurt locally here.

[skybrian]

It sounds like positive feedback loop. Some reason (usually jobs) results in higher density, which results in a shortage of housing and higher prices, and that’s an incentive to build denser housing so that more people can move in. The available workforce might attract more employers, and the loop continues.

You might as well ask how cities get started and grow larger. Contrast with farmers.

A positive feedback effect will keep going until there’s negative feedback counteracting it. That’s almost tautological. The specifics will be more interesting.

[engineer_22]

I hadn't thought of it like this before, but I think he's arguing that there is a network effect. High density is more convenient, which induces demand.

[hnboredhn]

I realize he is arguing for that but I think its pretty silly to have the chart there showing the correlation if so. He does address the point I made in the article but I think he dismisses it too fast without much evidence.

[engineer_22]

Ok I see what you mean

[hnboredhn]

I suppose to expound on my point more - the graph is by people not housing units. Presumably if a cheap city, like Detroit, had a bunch of unused units the graph would not credit it for the built-in density because if its not being used.

[quickthrower2]

It is harder for us tech workers to fathom, as we work for the global market directly or indirectly, the but a lot of people working in a city are directly serving other people in that city. A person coming in might create more than a jobs worth of “CityGDP” by their simple economic activity.

[seanhunter]

Yes exactly it is obvious. The article attempts to address this by saying this effect is not the full story, which seems highly unconvincing to me. His argument is stripped of density, Manhattan is just another island like lots of islands in Maine that didn’t end up having very expensive real estate. But firstly lots of islands (eg Martha’s Harbour, Long Island, which isn’t really an island but close enough) in the area are significantly less dense and have very expensive real estate so I don’t think that argument bears any scrutiny at all.

In general his thought experiments with data in the article just seem completely handwavy. “Imagine if I added 5x more houses to Oakland”. Well we can imagine that but we would likely be wrong about what would happen so it didn’t prove anything. Besides anything the most likely outcome would be you would have a lot of empty houses.

[ghaff]

Typically the building of housing and the use of land in fairly exclusive resort/beach/etc. communities is very tightly controlled. People in the Hamptons on the weekends don't want it to be another Manhattan. They already probably have a condo in Manhattan. Some real estate is desirable because of location (often beach/mountains) and community exclusivity--and often some degree of accessibility to wealthy population centers. (As you go up the Maine coast waterfront property is not necessarily outrageously expensive.)

[spacebanana7]

> But firstly lots of islands (eg Martha’s Harbour, Long Island, which isn’t really an island but close enough) in the area are significantly less dense and have very expensive real estate so I don’t think that argument bears any scrutiny at all.

This really depends on how you measure real estate prices. Long Island can have very low price per square foot of ground land compared to Manhattan, even if the unit price of housing or price per square foot of interior space is similar.