# Modeling Anchoring

Jarrett Walker has repeatedly called transit agencies and city zoning commissions to engage in anchoring: this means designing the city so that transit routes connect two dense centers, with less intense activity between them. For example, he gives Vancouver’s core east-west buses, which connect UBC with dense transit-oriented development on the Expo Line, with some extra activity at the Canada Line and less intense development in between; Vancouver has adopted his ideas, as seen on PDF-page 15 of a network design primer by Translink. In 2013, I criticized this in two posts, making an empirical argument comparing Vancouver’s east-west buses with its north-south buses, which are not so anchored. Jarrett considers the idea that anchoring is more efficient to be a geometric fact, and compared my empirical argument to trying to empirically compute the decimal expansion pi to be something other than 3.1415629… I promised that I would explain my criticism in more formal mathematical terms. Somewhat belatedly, I would like to explain.

First, as a general note, mathematics proves theorems about mathematics, and not about the world. My papers, and those of the other people in the field, have proven results about mathematical structures. For example, we can prove that an equation has solutions, or does not have any solutions. As soon as we try to talk about the real world, we stop doing pure math, and begin doing modeling. In some cases, the models use advanced math, and not just experiments: for example, superstring theory involves research-level math, with theorems of similar complexity to those of pure math. In other cases, the models use simpler math, and the chief difficulty is in empirical calibration: for example, transit ridership models involve relatively simple formulas (for example, the transfer penalty is a pair of numbers, as I explain here), but figuring out the numbers takes a lot of work.

With that in mind, let us model anchoring. Let us also be completely explicit about all the assumptions in our model. The city we will build will be much simpler than a real city, but it will still contain residences, jobs, and commuters. We will not deal with transfers; neither does the mental model Jarrett and TransLink use in arguing for anchoring (see PDF-p. 15 in the primer above again to see the thinking). For us, the city consists of a single line, going from west to east. The west is labeled 0, the east is labeled 1, and everything in between is labeled by numbers between 0 and 1. The city’s total population density is 1: this means that when we graph population density on the y-axis in terms of location on the x-axis, the total area under the curve is 1. Don’t worry too much about scaling – the units are all relative anyway.

Let us now graph three possible distributions of population density: uniform (A), center-dominant (B), and anchored (C).

Let us make one further assumption, for now: the distributions of residences and jobs are the same, and independent. In city (A), this means that jobs are uniformly distributed from 0 to 1, like residences, and a person who lives at any point x is equally likely to work at any point from 0 to 1, and is no more likely to work near x than anyone else. In city (B), this means that people are most likely to work at point 0.5, both if they live there and if they live near 0 or 1; in city (C), this means that people are most likely to work at 0 or 1, and that people who live at 0 are equally likely to work near 0 and near 1.

Finally, let us assume that there is no modal splitting and no induced demand: every employed person in the city rides the bus, exactly once a day in each direction, once going to work and once going back home, regardless of where they live and work. Nor do people shift their choice of when to work based on the network: everyone goes to work in the morning peak and comes back in the afternoon peak.

With these assumptions in mind, let us compute how crowded the buses will be. Because all three cities are symmetric, I am only going to show morning peak buses, and only in the eastbound direction. I will derive an exact formula in city (A), and simply state what the formulas are in the other two cities.

In city (A), at point x, the number of people who ride the eastbound morning buses equals the number of people who live to the west of x and work to the right of x. Because the population and job distributions are uniform, the proportion of people who live west of x is x, and the proportion of people who work east of x is 1-x. The population and job distributions are assumed independent, so the total crowding is x(1-x). Don’t worry too much about scaling again – it’s in relative units, where 1 means every single person in the city is riding the bus in that direction at that time. The formula y = x(1-x) has a peak when x = 0.5, and then y = 0.25. In cities (B) and (C), the formulas are:

(B): $y = \begin{cases}2x^2(1 - 2x^2) & \mbox{ if } x \leq 1/2\\ 2(1-x)^2(1 - 2(1-x)^2) & \mbox{ if } x > 1/2\end{cases}$

(C): $y = \begin{cases}(2x-2x^2)(1 - 2x + 2x^2) & \mbox{ if } x \leq 1/2\\ (2(1-x)-2(1-x)^2)(1 - 2(1-x) + 2(1-x)^2) & \mbox{ if } x > 1/2\end{cases}$

Here are their graphs:

Now, city B’s buses are almost completely empty when x < 0.25 or x > 0.75, and city C’s buses fill up faster than city A’s, so in that sense, the anchored city has more uniform bus crowding. But the point is that at equal total population and equal total transit usage, all three cities produce the exact same peak crowding: at the midpoint of the population distribution, which in our three cases is always x = 0.5, exactly a quarter of the employed population lives to the west and works to the east, and will pass through this point on public transit. Anchoring just makes the peak last longer, since people work farther from where they live and travel longer to get there. In a limiting case, in which the population density at 0 and 1 is infinite, with half the population living at 0 and half at 1, we will still get the exact same peak crowding, but it will last the entire way from 0 to 1, rather than just in the middle.

Note that there is no way to play with the population distribution to produce any different peak. As soon as we assume that jobs and residences are distributed identically, and the mode share is 100%, we will get a quarter of the population taking transit through the midpoint of the distribution.

If anything, the most efficient of the three distributions is B. This is because there’s so little ridership at the ends that it’s possible to run transit at lower frequency at the ends, overlaying a route that runs the entire way from 0 to 1 to a short-turn route from 0.25 to 0.75. Of course, cutting frequency makes service worse, but at the peak, the base frequency is sufficient. Imagine a 10-minute bus going all the way, with short-turning overlays beefing frequency to 5 minutes in the middle half. Since the same resources can more easily be distributed to providing more service in the center, city B can provide more service through the peak crowding point at the same cost, so it will actually be less crowded. This is the exact opposite of what TransLink claims, which is that city B would be overcrowded in the middle whereas city C would have full but not overcrowded buses the entire way (again, PDF-p. 15 of the primer).

In my empirical critique of anchoring, I noted that the unanchored routes actually perform better than the anchored ones in Vancouver, in the sense that they cost less per rider but also are less crowded at the peak, thanks to higher turnover. This is not an observation of the model. I will note that the differences in cost per rider are not large. The concept of turnover is not really within the model’s scope – the empirical claim is that the land use on the unanchored routes lends itself to short trips throughout the day, whereas on the anchored ones it lends itself to peak-only work trips, which produce more crowding for the same total number of riders. In my model, I’m explicitly ignoring the effect of land use on trips: there are no induced trips, just work trips at set times, with 100% mode share.

Let us now drop the assumption that jobs and residences are identically distributed. Realistically, cities have residential and commercial areas, and the model should be able to account for this. As one might expect, separation of residential and commercial uses makes the system more crowded, because travel is no longer symmetric. In fact, whereas under the assumption the peak crowding is always exactly a quarter of the population, if we drop the assumption the peak crowding is at a minimum a quarter, but can grow up to the entire population.

Consider the following cities, (D), (E), and (F). I am going to choose units so that the total residential density is 1/2 and so is the total job density, so combined they equal 1. City (D) has a CBD on one side and residences on the other, city (E) has a CBD in the center and residences on both sides, and city (F) is partially mixed-use, with a CBD in the center and residences both in the center and outside of it. Residences are in white, jobs are in dark gray, and the overlap between residences and jobs in city (F) is in light gray.

We again measure crowding on eastbound morning transit. We need to do some rescaling here, again letting 1 represent all workers in the city passing through the same point in the same direction. Without computing, we can tell that in city (D), at the point where the residential area meets the commercial area, which in this case is x = 0.75, the crowding level is 1: everyone lives to the west of this point and works to its east and must commute past it. Westbound morning traffic, in contrast, is zero. City (E) is symmetric, with peak crowding at 0.5, at the entry to the CBD from the west, in this case x = 0.375. City (F) has crowding linearly growing to 0.375 at the entry to the CBD, and then decreasing as passengers start to get off. The formula for eastbound crowding is,

(F): $y = \begin{cases}x & \mbox{ if } x < 3/8\\ x(5/2 - 4x) & \mbox{ if } 3/8 \leq x \leq 5/8\\ 0 & \mbox{ if } x > 5/8\end{cases}$

In city (F), the quarter of the population that lives in the CBD simply does not count for transit crowding. The reason is that, with the CBD occupying the central quarter of the city, at any point from x = 0.375 east, there are more people who live to the west of the CBD getting off than people living within the CBD getting on. This observation remains true down to when (for a symmetric city) a third of the population lives inside the CBD.

In city (B), it’s possible to use the fact that transit runs empty near the edges to run less service near the edges than in the center. Unfortunately, it is not possible to use the same trick in cities (E) and (F), not with conventional urban transit. The eastbound morning service is empty east of the CBD, but the westbound morning service fills up; east of the CBD, the westbound service is empty and the eastbound service fills up. If service has to be symmetric, for example if buses and trains run back and forth and make many trips during a single peak period, then it is not possible to short-turn eastbound service at the eastern edge of the CBD. In contrast, if it is possible to park service in the center, then it is possible to short-turn service and economize: examples include highway capacity for cars, since bridges can have peak-direction lanes, but also some peaky commuter buses and trains, which make a single trip into the CBD per vehicle in the morning, park there, and then make a single trip back in the afternoon. Transit cities relies on services that go back and forth rather than parking in the CBD, so such economies do not work well for them.

A corollary of the last observation is that mixed uses are better for transit than for cars. Cars can park in the CBD, so for them, it’s fine if the travel demand graph looks like that of city (E). Roads and bridges are designed to be narrower in the outskirts of the region and wider near the CBD, and peak-direction lanes can ensure efficient utilization of capacity. In contrast, buses and rapid transit trains have to circulate; to achieve comparable peak crowding, city (E) requires twice as much service as perfect mixed-use cities.

The upshot of this model is that the land use that best supports efficient use of public transit is mixed use. Since all rich cities have CBDs, they should work on encouraging more residential land uses in the center and more commercial uses outside the center, and not worry about the underlying distribution of combined residential and job density. Since CBDs are usually almost exclusively commercial, any additional people living in the center will not add to transit crowding, even as they ride transit to work and pay fares. In contrast, anchoring does not have any effect on peak crowding, and on the margins makes it worse in the sense that the maximum crowding level lasts longer. This implies that the current planning strategy in Vancouver should be changed from encouraging anchoring to fill trains and buses for longer to encouraging more residential growth Downtown and in other commercial centers and more commercial growth at suitable nodes outside the center.

# Local and Global Knowledge

Adonia Lugo has a post criticizing Vision Zero, an American movement that aims at reducing the number of pedestrian and cyclist deaths from car accidents to zero. Adonia makes a lot of criticisms regarding lack of diversity within US bike advocacy, which I’m not going to discuss because I’m only tangentially familiar with it, via the general urbanist connection to Streetsblog. Instead, I’m going to zoom on one criticism, in which Adonia also invokes transit: Vision Zero activists look to a slate of European countries for guidance on making streets safer, including Sweden (which, alongside Norway and Denmark, has nearly the lowest car accident death rates in the world), and Denmark and the Netherlands (which are famous for their urban cycling facilities). Adonia’s response is,

With my inclusion filter on, it sounded like another example of white bike advocates looking to Northern Europe for solutions instead of turning to urban communities in the U.S. to find out how they’ve managed to get by walking, biking, and using transit all these years.

This is where I lost sympathy. What Adonia is asking, essentially, is for more respect for her (and her peer group’s) local knowledge, which is based on American cities in which few people who can afford cars take other modes of transportation. In the entire US, the only city where significant numbers of people who can afford cars take public transportation is New York, and there is not a single city where significant numbers of people who can afford cars ride bikes to work. This means that any discussion of improving transit access must include at least some knowledge of what happens outside the US.

Local Knowledge and Denigration

The problem is that talking about what happens outside the US shifts the locus of expertise from people with local knowledge to people with global knowledge. If an American city talks about adopting ideas from one of its neighborhoods, or even from a nearby city, there’s a lot of local knowledge, in the form of people who live or have lived in that area, or know many people who live there, and can evaluate a policy as to its success or failure. Internationally, there isn’t any, outside specialized forums; even highly educated Americans are usually monolingual, have never lived outside the US, and aren’t really plugged into the political debates in other countries, except maybe Canada.

The result is denigration. I’m not very plugged into cycling advocacy, so I’m going to use public transit for concrete examples. I have accepted that whenever I propose that comes from another country, someone is going to say “that’s there, this is America.” I definitely got this response when I started proposing modernizing regional rail in New York: “you are not a real New Yorker.” New York is the worst in the US in that it resists any ideas from other cities, even domestically.

It’s ultimately a defense mechanism against something that’s literally foreign, which the activist cannot evaluate because they and the people they trust haven’t really seen this in action. Thus, many Americans choose to believe that US public transportation is not a failure, that it’s just in bad circumstances and has little to learn from Europe. I’ve seen New Yorkers make remarks such as “there is no history of underinvestment in Europe” (yes, there is – look at Berlin during the Cold War, or at the removal of streetcars in postwar France and West Germany).

For example, I’ve found that bringing up Stockholm as an example of good transit in the US gets me accused of trolling, repeatedly, more so than bringing up London or Paris. The reason is that, to New York-based readers, London and Paris are almost peer cities, and to other Americans, London and Paris are equivalent to New York; therefore, they match the perception that public transit works in old, huge cities, but not in smaller or newer ones. In some ways, I think Stockholm is a better example of what US cities should aspire to, precisely because it is a small city. It is also not as old as London or Paris; between 1950 and 2010, Stockholm County’s population grew by a factor of 1.9, whereas metro Philadelphia’s grew by a factor of about 1.6, Boston’s by a factor of 1.4, and Chicago’s by a factor of 1.7. Boston in particular had a very good public transit network in 1950, and it systematically dismantled it and bypassed the remains, so that the metro area public transit mode share is only 11%. Expressed differently, metro Boston has 55 annual rail trips per capita, whereas New York has 95 and Stockholm 200. Of course, the cities of the US Sunbelt have had far more postwar growth than Stockholm (though many are comparable to Vancouver) and even lower transit usage than Boston and Philadelphia, and there indeed wholesale imports of European ideas are less practical. But it says a lot that in the oldest US cities, with the street layout most similar to most of Europe’s cities’, transit usage is still very low.

Adonia denigrates ideas she considers racist, but this denigration cuts across political and tribal lines in the US. I have seen considerable denigration from American urbanists that city centers could ever be family-friendly whenever I mention generations of families living in the central parts of Tel Aviv, or Vancouver, or Stockholm. There’s even a Twitter account dedicated to this denigration, The Suburbanist. Of course, what’s missing is the history of white flight and racism – not that Israel, Canada, and Sweden are less racist than the US, but their racism did not involve leaving inner cities to low-income minorities. But mentioning that cities aren’t bad places for families reminds certain people that they’re leaving the cities because they don’t like minorities, so they lash out. Nowadays, the Suburbanist engages in open racism, but this wasn’t the case a few years ago, nor is it the case with a large number of Americans who, in comments on various blogs (never here as far as I remember), yell at me for bringing up foreign cities.

Not Invented Here, Periphery Version

When planners and managers denigrate foreign ideas, this is called Not Invented Here syndrome. It is common in American transportation planning. I believe the reason Vision Zero sticks to “it works in Scandinavia” is to at least try to confront those planners with the fact that, by international standards, they have failed to promote road safety, especially for pedestrians and cyclists. Certainly this is the reason I bring up the failure of every US city except New York to maintain respectable public transit usage.

Now, the two centers of public transportation innovation in the world – Europe and Japan – brim with their own NIH problems, toward each other. Their rolling stock markets are almost entirely distinct, due to a combination of protectionism and regulations. Japan is outside the European Train Control System umbrella and keeps developing its own signal systems, while ETCS in turn is based on the features of older systems in the major European countries and not in Japan. Japan lags Europe in automation (driverless metros are less common there), track capacity in trains per hour, and small-city cost-cutting innovations such as proof of payment. Europe in turn has higher big-city operating costs, more accidents, less punctual trains, and usually heavier trains. Both of those centers would benefit from adopting each other’s ideas.

And yet, things work. There is enough indigenous transit expertise in Japan that despite missing out on European innovations, Japanese transit systems work well. There has to be; Tokyo has comfortably not only the highest rail ridership in the world, but also the highest rail ridership per capita, about 400 annual trips, versus 200-250 in the most transit-oriented European cities. Of course, Europe’s own indigenous expertise is nothing to scoff at, either.

The US is not in the center of public transportation. I am going to develop this center-periphery dynamic in a later post, tentatively called Unbroken Country: The Periphery’s Manifesto, which will also go specifically into Israel’s domestic problems with public services. But, in short, the US acts as if it is in the center, since it is one of the centers of the global economy, and is the undisputed center of global society and culture. This is what leads to NIH syndrome and denigration – Americans think they’re doing well because, in most aspects, they are. But when it comes to transportation, the US is a peripheral region (even road construction techniques lag Europe’s), and thus, its NIH problems deprive the public discourse of much-needed knowledge.

For a concrete example, let us consider rail signaling. ETCS Level 2 is designed around the needs of the biggest European countries, where the main lines are at least double-track, there is much more passenger traffic than freight traffic, freight trains are light because bulk freight goes by sea, and the population density near the main lines is high. Neither the US nor Sweden fits this. Most importantly, both countries have highly-trafficked freight lines passing through remote territory – Norrland in Sweden, the Interior West in the US. Sweden, which does not have NIH syndrome with respect to the rest of Europe, worked on developing a lower-cost version of ETCS, called ERTMS Regional; but in the US, the freight railroads as well as the commuter railroads (even in the Northeast, where ETCS Level 2 is appropriate) ignored ETCS entirely and developed their own incompatible systems, on the grounds that ETCS doesn’t meet unique American needs.

The Mystery of the Foreign

People who don’t know something often consider people who do know it to be mysterious, almost magical. It is a commonplace that, in low-literacy cultures, illiterates viewed the written word as magical; see this account of Early Modern Italy, but also a counterpoint from Ancient Greece. Of course, literacy in the first world today is universal, but two to three more modern examples persist, of relevance to US transit advocacy:

1. Math, among people who are not mathematically- or technically-minded. I was asked recently whether my background as a mathematician influences my blogging, and explained that I use fairly basic math, but I am not afraid of numbers, which means I am not afraid of trying to compute cost figures, train speeds, and so on. I am also secure enough in my mathematical knowledge that I am not afraid of nitpicking technical points, or of being nitpicked.
2. Foreign languages, among monolinguals. I do not know enough monolingual Hebrew speakers to confirm this in generality, but monolingual Anglophones seem to treat foreign-language information as somewhat magical. For example, the vibe I have been getting both here and on Twitter is that if I cite a foreign-language Wikipedia this gets more respect than if I cite English Wikipedia. The monolingual Anglophone can verify an English Wikipedia citation, and maybe notice small mistakes in the article, but not a foreign-language citation.
3. This may be the same as 2, but, foreign experience. Relatively few native-born Americans have lived outside the US, so people who do are treated as having unique expertise about the country or continent they were in.

Point 3 applies even to knowledge obtained by other means than living in a country. In 2005, when progressive pundits were talking about how to implement universal health care, there was so little knowledge about how universal health care systems worked that Ezra Klein became an A-list pundit out of a few short profiles of various countries’ health care systems, The Health of Nations (see 2007 version here). I, of course, have gotten a lot of mileage out of Googling various cities’ subway construction costs and putting them together.

The problem with viewing the foreign as mysterious is that it leads to wholesale import of ideas that may not work, or may require significant tweaks before working. Bus rapid transit, an efficient mode of travel in middle-income Bogota and Curitiba, does not port to high-income cities well: paying six bus drivers rather than one train driver to avoid spending money on rail construction is a bigger problem in a country with a GDP per capita of $40,000 than in a country with a GDP per capita of$13,000. There are successful tweaks, such as open BRT (see description here), but Jaime Lerner and ITDP have pushed Curitiba-style closed BRT. Here, the lack of detailed knowledge about what exactly makes BRT work leads American cities – and no European or Japanese cities – to propose ill-thought closed BRT.

Another example of a bad import caused by this kind of magical thinking is the mixed-traffic streetcar. Here, American transit advocates don’t just think in terms of “Europe has trams” but also in terms of “the US used to have trams but we ripped them all up in the 1950s.” Here, US cities import a mode of transportation that exists as a legacy around Europe, but is uncommon on new-build lines, and is used mainly as a compromise when the streets are so narrow it’s impossible to give streetcars dedicated lanes without closing the streets to car traffic. As the US does not have cities with such narrow streets, outside a few old neighborhoods in Boston and New York with good subway service, its import of mixed-traffic streetcars is bad transit.

This relates to the point I made above, about local knowledge and bullshit. I know that many people view me as somewhat mysterious for having such a different knowledge base from Americans. It means I can comfortably bullshit about many points. I don’t bullshit, but it’s likely I’m making some mistakes, and I try to encourage my commenters to check me on them. But this requires commenters who are also very technically-minded and don’t think that just because I say something, it must be true.

Trust

In a sociopolitical environment in which the public and the activists have very little knowledge about imported ideas, whether they support them (usually viewing them as magical) or oppose them (usually denigrating them) is based on whether they identify with and trust the people proposing the import. Adonia does not trust the people who promote Vision Zero, since she views them as too white and male and too insensitive to the concerns of nonwhites, for example regarding police enforcement of speed limits. Conservatives, in turn, do not trust those people because they view them as cosmopolitan liberal urbanites, whence Tea Party opposition to various commuter and intercity rail expansions.

Consider high-speed rail, which is entirely a foreign import. The political coalitions for and against HSR in the US are based entirely on cultural identification with the proposition that Europe is better at something than the US. In particular, business-class small-government conservatives, who tend to be big fans of HSR in the countries where it exists, hate it in the US; George Will claimed it would make Americans more amenable to collectivism, and in Texas, right-wing populists have tried blocking an entirely private HSR scheme and possibly connecting it to the Democrats. In contrast, the populist left in the US (for example, Robert Cruickshank) supports public transportation infrastructure because of the environmentalist tie-in; in contrast, in the UK, Jeremy Corbyn, who Robert is otherwise a big fan of, is at best lukewarm toward HS2. In Europe, the left is more pro-rail than the right, but the populists on both sides are more anti-rail, and the overall left-right gradient is small; in the US, the left-right gradient is large, and this comes from the issue of trusting the transportation program of countries that Americans associate with welfare-state social democracy.

The result is that any dialog based on foreign transit has to involve a certain amount of mystery and trust in the planners. I have no trust in the planners, because of various wheel reinventions proposed even by reformists, but I know enough to discuss technical items and not just the people. Generally, other people with this technical background come from a similar social background: educated, geographically mobile, white, male. The result is that, as with HSR, people’s opinions on these projects track their opinions of the tribe in the US that can talk at this level of technical detail. Usually it’s not even racial, not when it comes to transit – it’s mostly suburbanites looking for ways to screw the urbanites. If anything, nonwhite neighborhoods in the US are underserved relative to best practices, and agencies sometimes sandbag the idea of more service there. Adonia just weaponizes this in a different direction from the usual.

Local and Global Knowledge

I’m not going to rule out the possibility that there is valuable local knowledge in the US about cycling, but I know that there is very little such knowledge about transit, and given where the high cycling use is, I doubt cycling is much different. This means that American knowledge alone is worth approximately nothing. Jarrett Walker is of course American and has a lot to contribute, but as a consultant, he has extensive Australian and Canadian experience and some East Asian experience. The bus grid as an idea predates Jarrett – Jarrett attributes it to (at least) 1980s-era reforms in Portland – but by itself it’s not a game changer.

The problem here is that to implement something successfully, the people who run it need both local knowledge and knowledge about places that work, i.e. global knowledge. If there aren’t enough people with both, the solutions will not work, because people who can’t contradict what the planners are saying can’t exercise democratic accountability over them. One of the reasons Europe does transit better is that there’s more foreign knowledge here; see above for the contrast between how the US and Sweden handle rail signaling.

In fact, if you look at the examples above in the Mystery of the Foreign section, they both come from failure to adapt a successful foreign system to local conditions – namely, high wages in the case of BRT, and wide streets in the case of trams. I presume that the people who build mixed-traffic streetcars and BRT lines in the US have plenty of local knowledge, but they lack the global knowledge to appreciate what exactly makes those systems successes abroad. Conversely, international consultants don’t have the local knowledge to say “no, this is not a good fit for your needs” (besides, usually that’s not what they’re paid to say). This problem is especially acute with innovations in developing countries, such as BRT, since the large gap in incomes leads to different situations requiring major changes in adaptation, much more so than the relatively minor differences within the developed world.

Now, consultants can pick up local knowledge. Their trade is not just to possess global knowledge, but also to know how to acquire local knowledge rapidly when they’re working in a city. They run surveys, look at detailed breakdowns of costs and ridership to tease out patterns, quiz the in-house planners, and travel all over the city to gain ground-level impressions. The problem is that if the consultants are the only people who have both local and global knowledge, then there is no democratic accountability, and they have an incentive to bullshit. Of course, Jarrett specifically does not bullshit, but he has occasionally made mistakes (the main one, anchoring, I’ve been meaning to write about for two years), and of course my personal trust in one consultant is no substitute to systemic, institutional trust in the ability of the technocrats to response to what is essentially peer-review practiced by the community of local advocates.

It means the only way forward is for activists in US cities to pick up global knowledge and engage with such plans on the details. In the case of cycling, I could think of any number of reasons why US cities cannot emulate the success of Amsterdam and Copenhagen; but then again, it’s possible these reasons are all irrelevant, in the same manner many reasons Americans offer for why they cannot have the same per capita transit usage of Sweden are irrelevant.

I am also suspicious of the fact that, per Adonia, bike advocates look to Northern Europe as a source of examples of success. The biggest bike share systems in the world are all in China, and in Japan, bikes have largely replaced buses as the preferred mode of access to the train station in the suburbs. US bike advocates owe it to themselves and to their cities to be informed about Chinese and Japanese practices, and, if they clash with Dutch and Scandinavian practices, then to have opinions about which ones to pick and how to synthesize them in a local context. The only way forward for people in the periphery, by which I mean all of the US when it comes to any non-car transportation, is to know how the core works well enough that they can adapt its innovation without being so reliant on outside experts.

# Cities and Immigration

There are various observations I would like to make about the urban geography of immigrants: where immigrants often land, what neighborhoods they prefer, how they differ both from the preference of natives, and how they differ from the policies that governments, run by enfranchised voters, implement. Many of the points I’m about to make I’ve made in comments before, on the Urbanophile and other urbanist blogs. I was compelled to write this by the news stories of the migration wave of Syrian refugees into Europe, but I would like to stress that I am writing about both labor migration and humanitarian migration, and that this post has been on my to-do list for years. The points here are often true of nearly all classes of immigrants: refugees, low-skill work migrants, high-skill work migrants; only family reunification is outside the scope of this post, but even family reunification usually consists of the family of a migrant immigrating as well.

The dominance of rich regions

Eurostat has regional per capita income figures for most of Europe. After subtracting rent and interest payments, incomes in London are 46% higher than in the United Kingdom as a whole, and twice as high as in depressed regions such as Birmingham and Sheffield. In Ile-de-France, the incomes are 38% higher than in France as a whole and 65% higher than in depressed regions such as Nord-Pas-de-Calais. In Northern Italy, the incomes are 80% higher than in Southern Italy, while if we compare the richer parts of the North (e.g. Lombardy) with the poorer parts of the South (e.g. Sicily and Naples), the gap grows to a factor of two, as in the UK. In all three countries, the rich regions have far more immigrants per capita than the poor regions. As of the 2011 census, 13.4% of the population of England and Wales is foreign-born, but in London, this rises to 36.7%. In France, 8% of the population consists of immigrants, but in Ile-de-France it rises to 17%: see PDF-p. 24 of an INSEE factsheet, and note also the table at the top of the page, showing far fewer immigrants live in rural areas than natives. In Italy, a breakdown per region shows 8-11% of the people in the Northern and Central regions are immigrants compared with 2-4% in the Southern ones.

Let us go over the reasons why. After all, in principle, both immigrants and natives are more interested in earning high incomes than in earning low incomes. So to see this, let us look at the situation from the point of view of someone who grew up in a poor region of such a country. The Brummie, the Sheffielder, and the Liverpudlian know that the Londoner makes more money than they do. But they can’t just move to London and expect to earn the same income a native Londoner earns. Their local social networks are precisely the ones they can rely on for job search tips, and after they’ve begun working they acquire local bosses who can give them reference letters, and neither group lives in London; this means that they’d make far less money than an equally qualified Londoner if they moved. This is on top of the personal disutility one suffers when moving, independently of the wage. This is less true of highly educated workers, who move in national and even international networks, whence the brain drain problem in rural and depressed areas.

Of course, immigrants short-circuit this, because immigrants usually come into the country without a social network in either its rich core or its depressed periphery. Logically, they go to where there are jobs, and to where the jobs pay more.

Immigrant networks

The situation I described above is true for first entrants. Once a community establishes itself in a city, the situation for the new immigrant changes. An Indian who wishes to emigrate to Canada can often rely on networks of Indian-Canadians, both first- and second-generation. This Indian’s situation is the exact opposite of that of the native of a depressed region: the native of Atlantic Canada, the poorest region of English Canada, has a social and professional network in their home area but not in Toronto or the other major cities; the Indian has a social network in Toronto and Vancouver but not in Atlantic Canada. This means that even when the income advantage of the traditionally rich cities disappears, immigrants will keep moving to them.

For three examples of this principle, let us look at the UK, Canada, and finally the US. In the UK, look at the table above again, and observe that, after London and the Southeast, the part of Britain with the highest foreign-born percentage is the West Midlands (the region, not the county), with 11.2%. This is because Birmingham used to be a rich city: Jane Jacobs compares it favorably with Manchester in The Economy of Cities, published in 1970. It declined in the 1970s, but by then the South Asian migration wave to Britain was already well underway. In Canada, Vancouver and Toronto remain rich, but Calgary has far surpassed them in incomes due to the oil boom, and is only now receiving comparable numbers of immigrants; 26% of its population is foreign-born, versus 40% of Metro Vancouver and 46% of the Greater Toronto Area (see data here). Finally, in the US, Los Angeles has remained one of the top destinations for immigrants, even though its incomes have slipped far below those of not only New York and San Francisco, but also Boston, Chicago, Minneapolis, Denver, and other cities that are only beginning to see the same immigration numbers Los Angeles has had for decades. In general, the states bordering Mexico have long had elevated numbers of Mexican immigrants, going back to the braceros and even before, ultimately tracing to the large Mexican presence in those states after the US conquered them in the Mexican War.

Once there is an established community of immigrants from a particular country or ethnic group, they of course encourage further migration, in addition to shaping the migration to reach the same regions and city neighborhoods. This can take the form of social networks for community support and for finding work, but also the form of knowledge of migration routes. See, for example, a Guardian article from yesterday explaining the Syrian migration wave as a result of years of social learning in Syria of the best routes for trekking into Western Europe. Conceivably this could also include legal knowledge of how to apply to asylum and which countries have the most favorable policies.

At the same time, as the national or ethnic community in the target country gets larger, it begins to exhibit domestic ethnic dynamics more than immigrant dynamics. Part of it is that the immigrants eventually naturalize and acquire voting rights and enough informal political power to have some influence over how their city is run. Part of it is that after a few decades there’s a rising cadre of well-assimilated second-generation immigrants. Part of it is that between the presence of a community and a natural trend of drift in which the relative incomes of cities in the target country change, immigrants eventually behave more like native Brummies and Sheffielders. As a result, most of what I say is true largely of recent immigrants, and gradually becomes less true of people who immigrated decades ago.

The primacy of work

Nearly all immigrants intend to work for a living. This is obviously true of work migrants, of all classes, but it’s also true of refugees, which leads many nativists to mock them for not really seeking asylum but taking jobs from natives. One particularly cruel article that appeared in my Twitter feed from multiple sources, proposing to detain asylum seekers and confine those who meet the criteria for refugees to restricted areas far from the job-rich core, makes the point that people who try to move to where there are jobs are (illegal) work migrants.

The reality is that one of people’s basic needs is work. Idleness is not a normal state of affairs for a person; when as many as a quarter of the people in the workforce are unemployed, it’s a depression and a national crisis. In developing countries there is a lot of covert unemployment, in the sense that (especially in rural areas) a large majority of workers may be redundant if first-world technology is imported, but people still work for a living and earn a wage. In India, to take an example of a third-world country in a state of peace, the unemployment rate was 2.7% as of 2013. To say that a migrant who wants work is necessarily a work migrant is equivalent to saying that a migrant who wants shelter is moving to the first world for its higher housing quality and that a migrant who wants their children to be able to go to school is moving to the first world for its better schools. This need for work drives everything: immigrants from poor countries will work under the table, take jobs far below their skill level, and scab, and they’ll make sure they stay employed, as they would at home, except that these compromises wouldn’t really be necessary, since the third world has much more unskilled work to do.

That said, the need to work in an environment where the migrant has no local social network is the primary determinant of where the migrant lives. Given free choice, immigrants tend to cluster where there is easy access to jobs, ideally on foot in order to avoid paying exorbitant sums of money for a car. A rapid transit network makes it easier for people to disperse; in its absence, as in Tel Aviv, the migrants will cluster in a few cheap central neighborhoods, but even when it exists, migrants will try living where they can get to work easily. The greatest concentration of immigrants in Ile-de-France is in Seine-Saint-Denis, an inner-suburban department that in most other countries would be an outer neighborhood of Paris.

Finally, I wish I didn’t have to explain this, but given that it’s a politically charged issue right now, we see a lot of nativist complaints that immigrants are not seeking work, but welfare. The above article is one example of the genre, ultimately defining every social service immigrants use, such as schools, as welfare. Another example is a report by the anti-immigration Center for Immigration Studies, which finds that under a definition of welfare that excludes programs used by retirees (i.e. a large majority of US social spending), immigrants to the US use welfare more than native-born Americans.

In the rest of this post, I will expound on what the primacy of work means for housing policy.

Housing choice, overcrowding, and prejudice

Within a given city, immigrants do not choose where to live on the same criteria as natives. First, and this applies to immigrants of all categories and even to some domestic migrants, they lack the prejudices of locals. New Yorkers know which neighborhoods of the city are good and which are bad, whatever good and bad mean. New York is globally famous due to the influence of American media; in Israel, all that’s penetrated the cultural barrier is that Manhattan is the center, Brooklyn exists and has a lot of Jews (I remember being puzzled at why Super Mario isn’t Jewish when I was 10), and Harlem is a poor black neighborhood. In 2006, a few weeks after I moved to New York, I was in Bedford-Stuyvesant for an event, and nothing about the neighborhood looked poor to me. With my American cultural knowledge today I’d be able to tell that project towers, certain kinds of bodegas, and large concentrations of black people in that part of Brooklyn all correlate with poverty, but at the time, I couldn’t. I’m not the only one: a white Canadian blogger I know who moved to New York a few years before I did walked around Bed-Stuy looking for an apartment and found it nice, and when they reported where they were on a forum, people’s reactions were a mix of horror and outrage: “you’re crazy, you could have been killed” and “you evil gentrifier.”

Second, as a subset of the principle that new immigrants are more likely to move to the rich core cities than to poorer peripheral cities, new immigrants tend to be in the center of the city than in the suburbs (and again, this also somewhat applies to domestic migrants). Suburban jobs often pay less – the highest-earners in the favored-quarter suburbs in the US commute to the primary CBD, whence for example Daniel Kay Hertz’s observation that in suburban Chicago and Philadelphia, transit riders (CBD-bound commuter rail riders) outearn drivers. Here, there is a split between skilled and unskilled migrants. Skilled migrants often move to a city because, in the specialized global economy, their skills are a good fit for its primary industry; this means that if they’re moving to the Bay Area, it’s usually to work in the software industry or at one of the universities, rather than to be lawyers or accountants, which means their housing choice is disproportionately oriented toward where those industries cluster. Unskilled migrants have to consider transportation costs, making it hard to live in the suburbs, and on top of that, unless they’ve already been matched to a suburban employer to get a work visa (for example, to work as a maid in a particular house), it’s easier for them to find work in the central city.

For migrants from developing countries, there is one more consideration, which leads to the most glaring feature of low-income immigrant neighborhoods: people in the third world make more compromises on housing space to have access to jobs, leading to overcrowding. It’s often a step up from where they’re from anyway. New York has a profile of each of its community boards, based on the most recent census; before the move from the long-form 2000 census to the short-form 2010 census, there was detailed data about income, education, and crowding in each census tract, and the most overcrowding in Manhattan was not in the poorest neighborhood (East Harlem) but in Chinatown.

The basic issue here is that low-income immigrants from developing countries are unlikely to make enough money to cover rent at what first-world natives consider a respectable living standard. There’s a certain minimum housing quality in the developed world: minimum unit size, insulation, indoor plumbing, electricity, construction materials. It’s hard to violate these regulations, because buildings are conspicuous – for the same reason, there’s no equivalent of Uber or Airbnb for housing that bypasses zoning laws. But as the Airbnb example shows, it’s easy enough to subvert or outright ignore regulations about who occupies a residential unit. Hence, immigrants economize on space, either living multiple unrelated adults to a room (as black refugees do in South Tel Aviv) or housing a large extended family in a suburban house meant for a nuclear family (as Hispanics do in various American suburbs, raising the ire of the local natives).

Transients

Many immigrants return to their countries of origin, or move elsewhere, after a few years. This fact is deemphasized in the public discourse, shaped by the US narrative of people from all over the world coming to live the American dream. But in reality, migration is often seasonal, and a significant fraction of immigrants return; see, for example, a write-up of Italian-American history. More recently, we see this with illegal Mexican workers in the US, who would move back and forth across the borders seasonally, until the tighter border controls built after 1986 made this so difficult they moved to the US permanently (this is the work of Douglas Massey, Jorge Durand, and Nolan Malone, summarized here and here). Many refugees return to their home countries after the war or crisis ends. Skilled migrants often move between countries, as I do.

This creates a situation in which many recent immigrants do not know where they will live in five years, not even on what continent, even excluding the possibility of deportation. This does not mean immigrants do not care about the areas they live in. On the contrary. But they lack the deep social ties that local neighborhood activists have, and this makes it harder to engage politically on a level that appeals to the local notables. It takes years just to learn who the local notables are!

Hence, the immigrant really is a transient. “Transient” is just a dysphemism for someone who does not have enough social capital in an area to know definitively that they’re going to stay there permanently. Unsurprisingly, since community decisions are made by people who know the local notables and their networks, those decisions do not have recent migrants in mind. Even domestic migrants, who unlike international ones have the right to vote, are excluded. This is where community hostility to more housing comes from: why worry about how high the rent is for people you look down on as transients?

As far as housing goes, YIMBY groups have begun to build a national US network for more construction, with some international reach, so that recent domestic migrants to New York, San Francisco, and other expensive cities can rely on their national social capital to compensate for their lack of local social capital. But this is necessarily going to address primarily the needs of the people who participate in YIMBY networks, who tend to be white, educated, and American. I happen to think more housing in a region will benefit all recent and prospective immigrants to it, but there’s a wealth of other local political issues that are not covered in the YIMBY umbrella (for example, policing), and there, the community’s ability to abuse residents who got here more recently than it would like is not limited.

Public housing

Finally, let me discuss the difference between how immigrants think and how governments elected by natives think immigrants ought to think. As I’ve established above, immigrants’ decisions are driven largely by the need for a job, even when the original purpose for the move was not work-related. This means that they will make compromises and live in a way that the native public deems substandard, as in various outrages of immigrant overcrowding.

The question is what to do about it. In capitalist countries (i.e. pretty much everywhere, except Cuba and a few other communist holdouts), the government professes to believe that people are economically rational. There are large sectors in which this is not true – for examples, health and education are mostly public in most developed countries – but in housing, most first-world countries use a free-market approach. Central cities often do provide extensive public housing, and zone tightly to prevent new construction that offends community sensibilities, but people can still buy and sell houses and move, and advocate for themselves politically so that they wouldn’t be stuck with housing that is by regional standards deficient.

Except, well, that people who lack voting rights can’t act politically except through their ties to enfranchised voters, and new migration waves lack these ties. The worst example of this is in Sweden, which provides refugees with public housing, but only where it’s cheap. Thus, instead of having a liberalized enough urban housing market so that refugees could live in overcrowded conditions in Stockholm, it either disperses them to peripheral towns where they know nobody and can’t work, or concentrates them in low-income ghettos. Malmö, which like Birmingham used to be a bustling city but deindustrialized and has high unemployment, is one of the prime locations for immigrants to Sweden; so is Södertälje, a Stockholm suburb infamous for its high unemployment.

One of the most salient features of being an immigrant is being a social problem. Every difference between the immigrant and the native will be used politically, in either direction, even if it is the result of normal variation between groups and economic sectors. And here, governments that refuse to consider immigrants’ own housing decisions are creating social problems for the future by creating new ghettos from scratch. For its own working class, Sweden built the Million Program; for immigrants, not a chance. Between overcrowding and joblessness, immigrants choose overcrowding, when they can. When they can’t, the government is choosing joblessness for them.

# Penn Station Elimination Followup

Several commenters, both here and on Streetsblog, have raised a number of points about my proposal to eliminate above-ground Penn Station and reduce the station to a hole in the ground. A few of those points are things I’d already thought about when I wrote that post and didn’t want to clutter; others are new ideas that I’ve had to wrestle with.

Waiting

On Streetsblog, Mark Walker says, “Getting on a train at Penn is not like using the subway. Instead of a train that runs every five minutes, you’re waiting for a train that runs once per hour (more or less),” implying nicer waiting areas and lounges are needed. My proposal, of course, does not have dedicated waiting areas. (That said, there’s an immense amount of space on the platforms under the escalators, which could be equipped with chairs, tables, and newsstands.)

However, I take exception to the notion that when the train runs every hour, passengers wait an hour. When I lived in Providence, a few trips to Boston, New Haven, and New York taught me the exact amount of time it’d take me to walk from my apartment to the train station: 21 minutes. I learned to time myself to get to the station 2 minutes before the train would leave, and as I recall, I missed the train twice out of maybe 30 trips, and one of those was when I had a lot of luggage and was in a taxi and couldn’t precisely gauge the extra travel time. Walking is that reliable. People who get to Penn Station by subway have to budget some extra time to account for missed subway trains, but from much of the city, including the parts of the CBD not within walking distance from Penn, the required spare time is less than 10 minutes. Moreover, Penn is at its most crowded at rush hour, which is precisely when subway frequency is the highest, and people can reliably time themselves to within less than 5 minutes.

Outlying train stations in Switzerland are deserted except a few minutes before a train shows up, because the connecting transit is all timed to meet the train. This is of course inapplicable at very large stations with many lines, but the modes of transportation that most Penn Station users take to the station are reliable and frequent, if you can even talk of frequency for walking. The result is that the amenities do not need to be extravagant on account of waiting passengers, and do not need to be more than those of a busy subway station in a busy area.

Shelter

Several commenters raised the idea of shelter. One option, raised by James Sinclair, is an arched glass roof over the station, on the model of Milan. This involves above-ground infrastructure, but the arched structure is only supported at the margins of the compound, which means that the primary feature of a hole-in-the-ground station, the lack of anything that the track area must support the weight of, is still true. I do not think it’s a bad idea; I do, however, want to raise three additional options:

Do nothing. A large proportion of the usable area of the platforms would be located under the walkways above, or under the escalators and staircases. Having measured the depth more precisely, through Plate 14 here, I found it is 13 meters from street level to top of rail, or 12 from street level to platform level, translating to 21 meters of escalator length, plus 2.2-2.5 meters on each side for approach (see page 23 here). About 16 of those 21 (18.5 out of 25.7, counting approaches) meters offer enough space for passengers to stand below the escalators, leading to large areas that could be used for shelter, as noted in the waiting section above.

Build a simple shelter. Stockholm-area train stations have cheap corrugated metal roofs over most of the length of their platforms. These provide protection from rain. Of course those roofs require some structural support at the platform, but because they’re not supposed to hold anything except rainwater, those supports are narrow poles, easy to move around if the station is reconfigured.

Build a street-level glass pane. This may be structurally intricate, but if not, it would provide complete shelter from the elements on the track level, greatly improve passenger circulation, and create a new public plaza. But in summer, the station would be a greenhouse, requiring additional air conditioning.

Note that doing nothing or building a simple shelter would not protect any of the track level from heat or cold. This is fine: evidently, open-air stations are the norm both in cities with hotter summers than New York (Milan is one example, and Tokyo is another) and in cities with colder winters (for example, Stockholm). Passengers are usually dressed for the weather anyway, especially if they’re planning on walking to work from Penn or from the subway station they’re connecting to.

Architecture

Multiple commenters have said that public art and architecture matter, and building spartan train stations is unaesthetic, representing public squalor. I agree! I don’t think a hole-in-the-wall Penn Station has to be drab or brutalist. It can showcase art, on the model of the mosaics on the subway, or the sculptures on the T-Bana. It can use color to create a more welcoming environment than the monotonous gray of many postwar creations, such as the Washington Metro. The natural sunlight would help a lot.

# The Ultimate Authoritarian Anti-Urbanism

Cairo is a dense megacity, without the infrastructure such cities require for high living standards. The city proper, according to Wikipedia, has 10 million people, living at a density approaching 20,000 per km^2, and the metro area has 20 million. With a subway system fit for a city a tenth its size, Cairo is heavily motorized for its income level, congested, and polluted. Despite high construction costs, urgent investment in public transportation is required. Ignoring this need, the current military government has just announced plans to build a new capital outside the city, eventually to house 7 million people, with all the public monuments of a planned city, at a cost of $300 billion (exchange rate dollars, not PPP), about the same as Egypt’s annual GDP. The first phase alone will be$45 billion.

Cairo itself is already suffering from neglect and disinvestment. There are 2 million cars in the city. This is enough to cause so much traffic congestion it costs Egypt 4% of its GDP. Cairo’s air pollution is legendary: pollution levels are akin to smoking a pack of cigarettes per day. At least as of 1997, lead pollution caused by cars using leaded gasoline reduced Cairene children’s IQ by 4 points. The poor transportation options have led to a housing crunch, forcing half a million people to live in a historic necropolis as squatters.

The Cairo Metro would be a solution to these problems to a large extent, but is very small relative to Cairo’s size: it has 3 lines, totaling 78 route-km. Other cities of comparable size have many hundreds of route-km of urban rail, with a handful of exceptions infamous for their sprawl (such as Los Angeles) or pollution (such as Sao Paulo). Despite its small size, the Cairo Metro gets about 1.6 billion passengers per year, by far the highest number of passengers per route-km in the world, nearly twice as high as on the legendarily overcrowded Tokyo subway. Cairo has high construction costs, but in exchange rate dollars they only amount to about $130 million per km; a fully underground expansion of the subway to 400 km, somewhat more than the length of New York’s subway lines and less than that of Beijing and Shanghai’s, would cost about$40 billion, less than the cost of the new capital’s first phase alone. This is on top of all other possible infrastructure investments Egypt should consider: sanitation, sewage, water treatment, electrification, hospitals, schools, the Suez Canal. I bring up the Metro since so many of Cairo’s pressing problems would be substantially reduced if it had the capacity to transport a large share of the city’s population.

The problem is that the Egyptian government’s first priority is not to serve the needs of the Egyptian population. It is an authoritarian military government; it is not accountable to the broad public. I bring this up, because it’s a necessary check on things I have said in the past, attacking local American governance as authoritarian. Andrew Cuomo and Chris Christie have the power to overrule useful spending bills and cause traffic jams in cities run by political opponents. Abdel Fattah al-Sisi has the power to jail political opponents without trial, and execute them by the hundreds after show trials.

Autocrats love planned cities, for two reasons. First, planned cities are monuments to their greatness, lasting long into the future. The people the autocrats trample will be forgotten. Tourists visit the Taj Mahal, and not museums commemorating the churches and temples Shah Jahan destroyed. They visit the Great Wall of China, and not any commemoration of the million-odd people who died in its construction. They visit the Old City of Jerusalem, while nobody commemorates any of the locals Herod taxed to build its monuments – even Judaism only commemorates the destruction of the Temple and the beginning of the Diaspora, generations later. Autocrats know this. Even in antiquity, they knew monuments would make them more famous. And even in modern democratic regimes, politicians like signature initiatives that have their names on them; going back to Andrew Cuomo, his proposed Queens convention center is a typical example. But Cuomo still faces some democratic checks and balances. Sisi does not.

And second, planned cities can be built in ways that enhance social control. City Metric compares the new planned capital with Naypyidaw, Burma’s capital, built in the era of military rule to replace Yangon. Purpose-built capitals can be (and are) built around the needs of the national elite, keeping the poor out of sight. They have street and building design plans that make it easy to bring in the military to quell riots: wide streets, buildings that do not touch, no central square where protests could happen. They also disallow squatters, without going through the difficult and controversial move of evicting squatters from the preexisting city. One rhetorical question I have seen on Twitter is, where will this city’s Tahrir be? An article on Cairobserver doesn’t make this exact argument, but does note that this plan disinvests in what will still remain Egypt’s largest city, and could only come about as a result of Egypt’s complete lack of democracy.

One of the bigger influences on my views of democracy is Brad DeLong and Andrei Shleifer’s paper from 1993, Princes and Merchants. I do not fully agree with the point they make, but one of the key components of it, on the spending priorities of an absolute ruler, is crucial to understanding the benefits of democracy. Per DeLong and Shleifer, absolutism chokes economic growth, since the absolute ruler will overtax the economy to maximize revenue. One may ask if actually, hereditary rulers would want to stimulate more economic growth in order to bequeath a stronger kingdom to their heirs. DeLong and Shleifer answer that no: even with clear rules of inheritance, succession wars are so common that kings have to constantly be on the guard against rebellion to make sure their heirs get to inherit anything.

For Sisi, it is perfectly rational to spend so much money building a capital city that would make an uprising against him less likely. The money is not going to come from his pocket, but from the pockets of people he need not care about too much – the Egyptian people. The personal benefits to Sisi are invaluable: Sisi’s two predecessors, Mohamed Morsi and Hosni Mubarak, were both overthrown and immediately charged with crimes, for which they were guilty (under Sisi’s influence, Mubarak was exonerated from most). Why not remove himself and the apparatus of the Egyptian state from the city where they were overthrown?

When I talk of infrastructure democracy in democratic first-world countries, I complain about (much) smaller versions of this exercise. One could reason with a democratic Egyptian government that there are better uses of the money in Cairo itself. One cannot reason this way with a military government. The same is true of the soft authoritarianism found in governments with a democratic deficit, from the European Commission to local American governments. Their power is ultimately limited by other layers of government, which are more transparent, and they are incapable of killing off political opponents, but they still do not have to listen to the people they impact, leading to decisions that are at times obviously ridiculous. Egypt’s new capital is this autocracy, taken to its logical end. A dictator, of the kind who the infrastructurists might praise as someone who can cut through the red tape and gets things done, is spending the country’s annual GDP on a plan to disinvest in the capital and build a monument to himself and his regime from scratch.

# Height Limits: Still a Bad Idea

In a pair of recent articles on Strong Towns, Charles Marohn, best known in the urbanist community for introducing the term stroad (street+road) for a pedestrian-hostile arterial street, argues for height limits as a positive force for urbanism. He does not make the usual aesthetic argument that tall buildings are inherently unpleasant (“out of scale”), or the usual urbanist one that tall buildings lead to neighborhood decline; instead, he makes an economic argument that allowing tall buildings greatly raises land costs, and makes redevelopment of vacant lots less likely. He uses the following example:

Let’s say the local code allows [a] vacant lot to be developed as a one story strip mall, but nothing higher. If the strip mall is worth $500,000, then the vacant lot is going to be somewhere around$75,000.

Okay, but what if the development code allows that vacant lot to be developed as a sixteen story tower? If the tower is worth $20,000,000, then that vacant lot is going to fetch a much higher price, maybe as much$2.5 million.

You own that vacant lot. I come to you with an offer to buy it for $75,000. What are the odds you are going to sell it at that price when you look to the other side and see the same piece of property going for millions? Not very good. In most cities, as Charles notes, there is not enough demand to redevelop every vacant lot as a high-rise, and therefore, if high-rises are permitted, a few vacant lots will be redeveloped as high-rises, while the rest remain vacant. This is not the case in large cities, which Charles specifically exempts in his article (see also Daniel Kay Hertz’s response), but part of the problem with the argument, as we will see, is that the boundary between large cities and small ones is fuzzy. Let me now explain why this argument fails, like all the other arguments for zoning restrictions: it makes implicit assumptions on future uncertainty. The reason the vacant lot owners are not willing to sell for$75,000 is that they hope to get $2.5 million. In a stable market, with low enough population that most lots cannot fetch such a high price, the lot owners know that holding off on$75,000 offers is a gamble and that they are unlikely to ever get a higher offer. People have optimism bias and might overrate the probability that they’ll get the $2.5 million offer, but also have risk aversion; in most cases in economics, risk aversion dominates, so that safer assets cost more and have lower returns. So when do we see holdouts? Risk aversion predicts that the probability of obtaining a$2.5 million offer should be higher than the total demand for new towers divided by the number of vacant lots. If we explicitly assume that the cost figures in Charles’ example, including land costs, are unchangeable, then this means vacant lot owners expect there to be more high-rise towers in the future, which comes out of growth regions. Charles’ example is based on Sarasota, which like most of Florida has high population growth.

The other possibility is regulatory uncertainty. In a competitive market, land costs are already as low as they can be while letting lot owners cash out on past investments. Developer profits are also as low as possible, and represent the developer’s wage for managerial work. However, zoning restrictions will greatly raise both figures, and a lot owner who expects future developments to brush up against the present zoning code can hold out until prices rise.

This is the danger of a system that is based on arbitrary rules (Charles proposes up to two floors or 1.5 times the average present height, whichever is higher), and arbitrary distinctions between small cities in which height restrictions are desirable and large cities in which they are not: these introduce political discretion in the details, which introduces additional uncertainty among lot owners. True windfalls usually involve the boundary between regulatory regimes, and this creates political incentive to game the system in order to be one of the few owners whose lots can be developed as high-rises. In contrast, once a ground rule is established that there is no zoning, such as in Houston, introducing zoning is difficult, even when there are rules that are zoning in all but name, such as parking minimums.

Once we get into the realm of cities with a large proportion of their lots developed, as Charles proposes, future development can only replace old development, and this introduces a key difference between new development and redevelopment: redevelopment requires buying out the preexisting property. If a two-floor building is replaced by a three-floor building, then the developer has to not only pay construction costs for three floors, but also buy out two floors, effectively paying for five floors. But the revenue is still only that of a three-floor building, which bids up effective costs by a factor of five thirds. The formula is that if it’s possible to multiply the total built-up area by a factor of $x$ then the buy-out factor will raise the cost of each housing unit by a factor of $1 + 1/x$.

This effect is why, in major cities, we usually see buildings replaced by much larger buildings: for example, a three- or four-floor Manhattan building may be replaced by a fifteen- or twenty-story tower on a base. Charles laments that this is not small-scale or incremental, but even his example of good incremental development is similar: in Houston, single-family houses are replaced by low-rise apartment buildings, generating similarly high ratios of the floor areas of redevelopments with the buildings they replaced. Incrementalism in these cases consists of replacing small buildings by much larger ones, gradually, until a few decades later the entire neighborhood is tall.

One way around redevelopment’s need to buy out preexisting buildings is to mandate that future buildings be built to allow adding floors on top of them. Chicago’s Blue Cross Blue Shield Tower is an example. This is a regulation that increases the average cost of construction but reduces the marginal cost and thus the price. It’s also a regulation that only really matters in situations when it is difficult to have a high ratio of new to old floor area, such as in areas that are already high-rise, especially major city CBDs. (It is easy to quintuple floor area ratio when the preexisting buildings have three floors, but not so much when they have twelve.) The current styles of construction of most small buildings, for example sloping roofs common in American and European urban and suburban houses, tend to make adding floors impossible. Of course, the implication that such a regulation should only apply for buildings above a certain height introduces political discretion and hence uncertainty, but at least this is uncertainty that would apply equally to all buildings in an area, which is not always the case for zoning.

What Charles proposes, to develop all vacant lots first and only then start going taller, is then a recipe for high marginal costs, because of the buyout factor. In a small city uniformly developed up to one or two floors, it is difficult to spread the new development across many buildings up to three floors, precisely because there is no way to build single-family houses that are recognizable as such to Americans or Europeans from countries I’ve been to (It’s different in Canada, but this is considered a feature of the low quality of Vancouver’s housing) and that can have floors added to them. In such an environment, building tall is the only way to avoid high housing costs.

# The NITBY Problem

Usually, the barrier to new development in a neighborhood is NIMBYism: connected local community members do not want the project, saying “not in my backyard.” There’s a wealth of literature about NIMBYs’ role in restrictions on development; William Fischel’s work is a good start, and the short version is that opposition to development is local, based on fear of the risk of decline in property values. Urbanists take it for granted that decisions made with regard to regional rather than local concerns will be more pro-development: Let’s Go LA has examples from Los Angeles, and Stephen Smith explains Toronto and Tokyo’s lax rules on new development based on their high-level decisionmaking (at the provincial level in Ontario and national level in Japan). In this post, I would like to discuss the opposite problem, which I call NITBYism – “not in their backyard.”

In certain circumstances, opposition comes from people living in other areas, who are aghast that an area they don’t live in is getting so much investment. This is more likely to happen when there’s heavy public involvement in development, but, since upzoning an area is a public decision (as opposed to unthinkable across-the-board zoning abolition), opposition can sprout anytime. One common thread to NITBY opposition campaigns is that NITBYs view housing as a good thing, and want it redirected to their areas. Another is that they self-perceived as ignored by the urban elites; this is common to both right-wing populists and left-wing ones. Since the process is heavily public by assumption, the price signal telling developers to build in the center of the major city is irrelevant, and this encourages the government to build more low-value peripheral projects.

The first example of this is when the process actually is public: subsidized affordable housing. As discussed by Daniel Kay Hertz, in Chicago, affordable housing regulations require developers to pay a fee to a dedicated affordable housing fund, which then uses the money to develop or buy housing and rent it out at subsidized rates for moderate-income residents. To minimize the cost per affordable unit, the fund builds the units in the cheapest neighborhoods, i.e. the poorest ones, exacerbating housing segregation. As Payton Chung explains, the low-income housing community networks in Chicago support this arrangement, because they are based in the neighborhoods where this affordable housing is built. This is not as self-serving as the examples I will include below, since the community groups want to see the most number of housing units built at a given cost; but a common feature of NITBYism, namely that the NITBYs view housing as a good rather than as a burden imposed by outsiders, is present here.

In Israel, NITBYism does not have the cost defense that it does in Chicago. Zoning in Israel is prepared by municipalities but must get approved by the state. This means that it is geared not only toward providing services to Israelis (such as cheap and orderly housing) but also toward national goals of Judaization. The worst NITBYism is not affecting Tel Aviv, but Arab cities, where the state refuses to approve zoning plans; since independence, not a single new Arab city has been built, except to house Bedouins who the state expelled from their villages after independence, and plans to build the first new Arab city are controversial on segregation grounds. This is while the state has built many new Jewish cities from scratch, often in peripheral areas in order to ensure a Jewish majority.

However, NITBYism afflicts housing in Tel Aviv, too. Although the state could if it wanted declare a housing emergency and force upzoning in Tel Aviv, it does not. There are few permits for new apartments in the Tel Aviv District (though more new housing sales): only 5% of the national total (including settlements), as per the pie chart on page 17 of the Ministry of Construction and Housing’s report and the more complete (in English) data on page 49, compared with a national population share of 16%; the Center District, consisting of Tel Aviv suburbs (though not the richest and most expensive, such as Ramat HaSharon, which are in the Tel Aviv District), has 22% of national permits, about the same as its share of the national population. This is not just NIMBYism in Tel Aviv, although that exists in abundance. Local politicians from peripheral towns demand local construction, and view Tel Aviv construction as something useful only to outsiders, such as foreign speculators or the urban elite. During the housing protests of 2011, there was widespread debate on the left about what solutions to offer, and people representing the ethnic and geographic periphery were adamant that the state build and preserve public housing in peripheral towns and not concentrate on Tel Aviv, which they identified with the secular Ashkenazi elite. A common thread in housing and infrastructure debates to both working-class Jews from the periphery and Arabs is the demand for a policy that would create jobs and housing in their hometowns, rather than build infrastructure that would put them in the Tel Aviv orbit.

Of the above examples, in Chicago the NITBYs self-identify as leftists, and in Israel, the NITBYs who want local housing rather than Tel Aviv housing either identify as leftists or identify as economic leftists and support the right on security and ethnic identity issues. However, the populist right is not immune from this. Right-wing supporters of suburbs who oppose cities for what they represent (diversity, usually left-wing politics of the kind they associate with the liberal elite) may also oppose urban upzoning. The best example of this kind is Joel Kotkin’s opposition to upzoning in Hollywood, which sounds like a criticism of government projects until one realizes that upzoning simply means developers are permitted to build more densely if they’d like. Now, Kotkin is pro-immigration, setting him apart from the main of right-wing populism, but in all other aspects, his paranoid fear of urban liberal elites imposing behavioral controls on ordinary people would be right at home at the UK Independence Party and its mainland European equivalents. Kotkin is also just one person, but his views mirror those of Tea Party activists who equate dense urbanism with an Agenda 21 conspiracy, to the point of conflating a phrase that means building new suburbs with a plan to forcibly relocate suburbanites to central cities.

I do not know Japan’s regional patterns of politics well, but I know Ontario’s. In Ontario, there is not much us-and-them politics regarding Toronto. There is such politics regarding the inner parts of Toronto – Rob Ford was elected on the heels of an outer-urban populist backlash to David Miller’s urbanism, including the perception that Miller was fighting a war on cars. But there’s none of the hatred of the central city and all that it represents that typifies politics in both Israel and the US. Hatred of the city in the US is right-wing (though within the city, hatred of the gentrified core is often tied to left-wing anti-gentrification activism), and hatred of Tel Aviv in Israel is generically populist, but in both cases, the us-and-them aspect encourages NITBYism.

In the most expensive American cities, this is not a major problem. Anti-urban populism does not have enough votes to win in New York and California, so state control of zoning in those states would not produce these problems. The Tea Party disruption of zoning meeting I brought up above happened in San Francisco suburbs, but did not have an effect on planning; I brought this example up to show that this political force exists, even if in that specific locality it is powerlessly weak. In those areas, local NIMBYism is a much bigger problem: many New York neighborhoods were actually downzoned in the Bloomberg era by local request. The primary problems that would plague state-level decisionmaking are corruption and power brokering, in which politicians hold even straightforward rule revisions hostage to their local pet projects. The us-and-them politics of Upstate and Downstate New York contributes heavily to power brokering, but Downstate’s demographic dominance precludes ideological choking of development.

Within the US, the risks of NITBYism are different. First, in the cost tier just below that of New York and California there are city regions in more moderate states, for examples Philadelphia and the Virginia suburbs of Washington, or possibly Miami (where the county-made rules have allowed aggressive new construction, mostly urban, which Stephen Smith credits to the political power of Cuban immigrants). And second, zooming in on different neighborhoods within each expensive city, the Chicago example suggests that if New York and other expensive cities begin a major program of public housing construction, the community organizations and the populists will demand to spread construction across many neighborhoods, especially poor ones, and not in the neighborhoods where there is the most demand.

As I noted two posts ago, there is a political economy problem, coming from the fact that the politically palatable amounts of construction are not transformative enough to let the working class live in market-rate city-center apartments, not in high-income major cities. Israel could semi-plausibly double the Tel Aviv housing stock; even that requires housing forms that Israelis associate with poverty, such as buildings that touch, without side setbacks. This would allow many more people to live in Tel Aviv, but they’d be drawn from the middle class, which is being priced out to middle-class suburbs or to working-class suburbs that it gentrifies. The working class in the periphery would be able to move into these closer-in suburbs, but this cascading process is not obvious. Worse, from the point of view of community leaders, it disrupts the community: it involves a churn of people moving, which means they end up in a different municipal fief, one with leadership the current suburb’s leaders may be hostile to.

For essentially the same reasons, subsidized housing in the center produces the same problems. If Israel builds a massive number of subsidized or rent-regulated apartments in Tel Aviv, there will be immense nationwide demand for them. Few would serve the residents of a given peripheral suburb, and there is no guarantee anyone would get them. On the contrary, in such a plan, priority is likely to go to downwardly-mobile children of established residents. At the 2011 protests, the people who were most supportive of plans to lower rents in Tel Aviv specifically were people from Tel Aviv or high-income suburbs who wanted to be able to keep living in the area. The community disruption effect of offering people the ability to live where they’d want would still be there. Thus, all the incentives line up behind periphery community leader support for building public housing in the periphery, where there is little demand for it, and not in the center. Even when housing is universally seen as a benefit and there’s no NIMBYism, politics dictates that housing is built in rough proportion to current population (since that’s where political power comes from) and not future demand.

Abolishing zoning is one way to cut this Gordian knot; it is also completely unpalatable to nearly everyone who is enfranchised in a given area. Allowing more private construction is the more acceptable alternative, but leads to the same problems, only on a smaller scale. It really is easier for community leaders to twist arms to demand veto rights and local resident priority than to push for sufficient citywide upzoning to alleviate the price pressure. But in an environment with weak NIMBYs and few NITBYs, fast growth in urban housing is possible.

# Pedestrian Observations from Central Stockholm

I like Stockholm. There’s something reassuringly familiar about it, despite the language barrier, which I think comes from the fact that the Central Stockholm housing stock is of similar vintage as the residential parts of Manhattan. It even avoids New York’s most annoying (to me) architectural tic, the exposed brick. The buildings here are similar in style to the ones in New York (and more generally northern Europe), but most have smooth exterior, with enough variation of colors between buildings to make it interesting.

The streets here vary a lot in width, but outside the older sections of the city, they are never very narrow. In Gamla Stan (“the old town”), the medieval core of the city that is now a tourist ghetto, complete with stores selling Swedish flags or English-language books, there are some pedestrianized streets with single-digit building-to-building width. But in my part of the city – Roslagstull, near the outer end of what’s considered Central Stockholm – the street width ranges are almost identical to those of Manhattan. My street, Birger Jarlsgatan, is about 30 meters wide, while less important parallel streets are about 15 or 20. Like the rest of city center, it’s lined with almost uniformly mid-rise buildings, six to seven stories tall. See photos here, from Södermalm, and here, from Regeringsgatan, a street that for a portion of its length is elevated over intersecting streets.

A feature of Stockholm streets that I have not seen in other cities is that on-sidewalk bike lanes. While the overall sidewalk width on Birger Jarlsgatan is generous, the sidewalk is broken by the bike lane. The inner side of the bike lane is interrupted by trees, and the outer side by sidewalk cafes, and as a result, sometimes walking in the bike lane is unavoidable if one wishes to avoid walking in zigzags. In any case, cyclist traffic does not seem to be heavy; there is much more pedestrian traffic.

Crossing the street is rarely difficult. There are beg buttons at intersections, but the pedestrian light will turn green even without pressing them. The stoplight phasing is simple: most of Central Stockholm is on one of several grids, and even at intersections of two-way streets (one-way streets are uncommon, at least around Roslagstull), there are only two phases per stoplight cycle. Without grade-separated freeways in the city core, the worst streets for the pedestrians are the occasional freeway-like structure, or one of several excessively wide roads. I walk to work on one of those roads, Valhallavägen, and during the daytime, the cars’ noise and air pollution are uncomfortable unless I walk through the parking lots behind the street or the bus bay in its median.

The transit system is useful, though I almost never take it. This is a combination of very high fares (with my pay-per-ride smartcard, I pay 25 kronor per ride, about PPP$2.70) and a city core that’s small enough and pedestrian-friendly enough that I can get around most of it on foot. The pedestrian orientation of the streets matters: my apartment is 2.3 km from the CBD mall and 1.7 km from Stockholm University; but I will walk to the mall, whereas to get to and from a conference at SU, I didn’t walk on Roslagsvägen (which is almost a full freeway) but instead took the subway from my university, KTH, which is more centrally located within the city. Of course, most people in the region don’t live in Central Stockholm, and for them the T-bana is a lifeline. Subway ridership here, excluding commuter rail, is about 900,000 per day (not weekday), not much lower than on the U-Bahns of much larger Berlin and Munich. As a curiosity, there are many light rail lines that connect outlying suburbs to a T-bana station, requiring a transfer to get to the CBD; the busiest, Roslagsbanan, is a narrow-gauge commuter rail system terminating next to KTH, with one T-bana branch, the T14, running parallel to it for a few stops before terminating. This is in addition to a mainline commuter rail system, with 267,000 daily passengers; this ratio of about one commuter rail rider to three subway riders is higher than anything most (see first two comments) in North America, but is much lower than in major European transit cities like Paris and London, where commuter rail and the metro have roughly equal ridership levels. Among the transit projects under construction in Stockholm is a new rail tunnel, which will increase the capacity of commuter rail. # Dispersing Expensive Centers: Edge City Version This is somewhat of an addendum to my post before about dispersal of urban networks toward cheaper cities. I addressed the question of dispersal from rich, expensive metro areas, especially San Francisco, to cheaper ones, as a way of dealing with high housing prices. But more common is dispersal within metro areas: gentrification spilling from a rebounding neighborhood to adjacent neighborhoods that remain cheaper, and office space spilling from the primary CBD to the edge cities. I am going to address the latter issue in this post. CBDs are expensive. They have intense demand for office space, as well as high-end retail and hotels. In many cities, there’s demand for office space even at the construction costs of supertall skyscrapers, going up to about$5,000-6,000 per square meter in privately-built New York towers. Zoning regimes resist the height required to accommodate everyone, and this is worse in Europe than in North America and high-income East Asia. Paris proper has many towers just above the 100 meter mark, but only three above 120. On a list of the tallest buildings in Sweden, not a single one above 100 meters is in central Stockholm, and the tallest within the zone are not in the CBD but in Södermalm; compare this with Vancouver, a metro area of similar size. But in the US, too, expanding CBDs is difficult in the face of neighborhood opposition, even in Manhattan.

The solution many cities have adopted is to put the skyscrapers in edge cities. Paris famously built La Defense, which has far more skyscrapers than the city proper does; Stockholm is building skyscrapers in Kista; London built Canary Wharf; Washington, the major US city with the tightest CBD height limits, sprouted skyscraper clusters in several suburbs in Maryland and Virginia. Ryan Avent proposed this as one solution to NIMBYism: in new-build areas, there are few residents who could oppose the new development. In contrast, near zoning-constrained CBDs, not only are there many residents, but also the land is so desirable that they are typically high-income, which means they have the most political power to oppose new development.

The problem with this solution is that those secondary CBDs are not public transit hubs. In Paris, this has created an east-west disparity, in which people from (typically wealthy) western suburbs can easily reach La Defense, whereas people from poorer ones need to take long RER trips and often make multiple transfers. In every transit city, the CBD is unique in that it can be reached from anywhere. To give similar accessibility to a secondary center, massive investment is required; Paris is spending tens of billions of euros on circumferential regional rail lines to improve suburb-to-suburb connectivity, expand access in the eastern suburbs, and ameliorate the east-west imbalance (see for example isochrones on PDF-pp. 20-21 of the links here). Those lines are going to be well-patronized: the estimate is 2 million daily passengers. And yet, the east-west imbalance, if nothing else, would be a lesser problem if instead of building La Defense, Paris had built up Les Halles.

The situation in other cities is similar. Kista is on one branch of one subway line, two stops away from its outer terminus. Living in Central Stockholm, my coworkers and I can get to KTH on foot or by bike, but a coworker who teaches at KTH’s satellite campus in Kista has a long commute involving circumferential buses (taking the subway and changing at T-Central would be even longer because of the detour). While many individual sub-neighborhoods of Central Stockholm are quite dense, the overall density in the center is not particularly high, certainly not by the standards of Paris or New York. A similar problem happens in Washington, where the biggest edge city cluster, Tysons Corner, is traditionally auto-oriented and was only just connected to Metro, on a branch. This always affects poorer people the worst, as they can’t afford to live in the CBD, where there is easy access to all secondary destination, and often are pushed to suburbs with long commutes.

There is a political economy problem here, as is usually the case with zoning. (Although in the largest cities skyscraper heights are pushing beyond the point of constant marginal costs, purchase prices at least in New York are much higher than construction costs.) The people living near CBDs, as noted before, are usually rich. The displacement of office space to the suburbs affects them the least, for three reasons. First, if they desire work within walking distance or short subway distance, they can have it, since their firms typically make enough money to afford CBD office rents. Second, since they live in the transit hub, they can access suburban jobs in any direction. And third, if the transit options are lacking, they can afford cars, although of course traffic and parking remain problematic. Against their lack of incentive to support CBD office space, they have reasons to support the status quo: the high rents keep it exclusive and push poor people away, and often the traditional mid-rise buildings are genuinely more aesthetic than skyscrapers, especially ones built in modernist style.

These concerns are somewhat muted in the US, where rich people decamped for the suburbs throughout the 20th century, and have supported zoning that mandates single-family housing in the suburbs, instead of staying in the city and supporting zoning that keeps the city mid-rise. This may have a lot to do with the formation of high-rise downtowns in American cities of such size that in Europe they’d be essentially skyscraper-free.

However, what’s worse in the US is the possibility of short car-free commutes to the edge cities. Where La Defense is flanked by suburbs with high residential density, and Kista’s office blocks are adjacent to medium-density housing projects for working- and middle-class people, American edge cities are usually surrounded by low-density sprawl, where they are easily accessible by car but not by any other mode of transportation. This is because the American edge cities were usually not planned to be this way, but instead arose from intersections of freeways, and developed only after the residential suburbs did. As those edge cities are usually in rich areas, the residents again successfully resist new development; this is the point made in Edgeless Cities, which notes that, in major US metro areas, growth has been less in recognizable edge cities and more in lower-density edgeless cities.

As with the possibility of dispersing innovation clusters from rich, expensive metro areas to poorer and cheaper ones, the already-occurring dispersal from city centers to edge and subsequently edgeless cities has negative effects. It lengthens transit commutes. Although in Tokyo, long commutes first arose as a problem of a monocentric CBD, and the city developed secondary CBDs as a solution, the situation in European cities an order of magnitude smaller is very different. It worsens housing segregation: the development of an edge city tends to be in the direction of the favored quarter, since that’s where the senior managers live, and conversely, higher-income workers can choose to move nearby for the short commute. Although nearly all metro areas have favored quarters, decentralization of jobs thus tends to lengthen the commutes of poor people more than those of rich people.

This is not quite the same as what happens when entire metro areas are forced to disperse due to housing cost. The agglomerations generally stay intact, since an entire industry can move in the same direction: smaller cities have just one major favored quarter with edge cities, and larger ones still only have a few, so that industries can specialize, for example in New York, biotech and health care cluster in the Edison-Woodbridge-New Brunswick edge city. Moreover, the specialized workers are usually high-income enough that they can stay in the central city or migrate to the favored quarter. San Francisco’s programmers are not forced to move individually to faraway poor neighborhoods; they move in larger numbers to ones near already gentrifying ones, spurring a new wave of gentrification in the process; were they to move alone, they’d lose the access to the tech shuttles. The negative effects are predominantly not on richer people, but on poorer people.

The problem is that even among the poor, there is little short-term benefit from supporting upzoning. If Paris, London, and Stockholm liberalize housing and office construction, the first towers built of both kinds will be luxury, because of the large backlogs of people who would like to move in and are willing to pay far in excess of construction costs. I am going to develop this point further in two posts, on what is best called NITBYism – Not In Their Backyard – but this means that the incentive for poor and peripheral populations is not to care too much about development in rich centers. The marginal additional building in a rich city center is going to go to the upper middle class; sufficient construction would trickle to the middle class; only extensive construction would serve the working class, and then not all of it.

In the US, the marginal additional building may actually displace poor people, if no new construction is allowed, simply by removing low-income apartments. It may even create local demand for high-income housing, for example by signaling that the neighborhood has improved. In San Francisco, this is compounded by the tech shuttles, as a critical mass of Silicon Valley-bound residents can justify running shuttles, creating demand for more high-income housing.

The amount of construction required to benefit the bottom half of the national income distribution is likely to be massive. This is especially true in France and the UK, which have sharp income differences between the capital and the rest of the country; their backlogs of people who would like to move to the capital are likely in the millions, possibly the high millions. Such massive construction is beyond the pale of political reality: the current high-income resident population is simply not going to allow it – when forced to share a building with the working class, it pushes for poor doors, so why would it want zoning that would reduce the market-rate rent to what the working class would afford? The only political possibility in the short run is partial plans, but these are not going to be of partial use to the working class, but of no use to it, benefiting the middle class instead. As a result, there is no push by the working class and its social democratic political organs to liberalize construction, nor by the small-is-beautiful green movement.

Ultimately, the attempt to bypass restrictions on urban CBD formation by building edge cities, like every other kludge, is doomed to failure. The fundamental problem of rich people making it illegal to build housing nearby is not solved, and is often made even worse. The commutes get worse, and the inequality in commutes between the rich and the poor grows. Office space gets built, where otherwise it would spread along a larger share of the medium-rise CBD, but for most workers, this is not an improvement, and the environmental effects of more driving have negative consequences globally. And once city center is abandoned to the rich, there is no significant political force that can rectify the situation. What seems like a workaround and an acceptable compromise only makes the situation worse.