Wednesday, April 8, 2015

Gell-Mann Amnesia among urban planners

From Mass transit isn’t necessarily the answer to lower carbon emissions by Bobby Magill. Urban planners have long suffered from a surfeit of planning enthusiasm, a deficit of data and a profound aversion to measured results and real accountability.

Everyone has lots of good ideas as long as you look only at the benefits column and ignore the costs. While the issues that urban planners deal with are real and material and begging for good answers, it is unicorn-rare to find evidence-based urban policies. Wishful thinking is the tune of the ball.

Enthusiastic idealists are Thomas Sowell's bête noire, routinely savaged in his books such as Intellectuals and Society, A Conflict of Visions, Economic Facts and Fallacies, The Quest for Cosmic Justice, The Vision of the Annointed: Self-Congratulations as a Basis for Social Policy.

Christopher J. Coyne has an excellent chapter in his Doing Bad by Doing Good: Why Humanitarian Action Fails comparing the custom of linear thinking versus systems thinking. In linear thinking, the flow of thought is, well, linear. If I contribute inputs A, B, and C, I can automatically expect outcomes X, Y, Z as a matter of course. Linear thinking works reasonably well in the material world such as manufacturing. It works not at all in the world of complex, dynamic, multi-causal systems. Basically, anything in which humans are involved. In complex systems there are hidden feedback loops, exquisite sensitivities/tipping points, contextual dependencies, cascading effects, etc. Inputs lack any clear direct relationship with outputs. You can't, for example, mandate everyone receive twelve years of standard and identical education and anticipate that the outcomes will have any uniformity or predictability.

Urban planners tend to be linear thinkers and many of their propositions make perfectly logical sense but they don't produce the results expected, and often produce undesirable results. It is also a field plagued with small studies that are neither robust or replicated.

Magill reports on one such study that overturns some of the long held assumptions of urban planners.
A Boston University study published on April 6 in the Proceedings of the National Academy of Sciences shows that a major push in cities like Denver to build dense housing, better transit systems, and more bike lanes in their urban core doesn’t necessarily lead to lower per-capita CO2 emissions. That’s because suburbs continue to sprawl and residents there still drive to work.

“For the past 25 years, urban planners have been guided by the results of analyses that show how per capita emissions vary with population density across different cities because time-series data for individual cities’ emissions simply were not available,” Ian Sue Wing, associate professor of earth and environment at Boston University and a study co-author said.

The study fills that gap and shows that cities like Denver or Salt Lake can’t quickly become like New York or San Francisco in terms of vehicle emissions per person, he said.

Expanding low-density cities often add population far from centers of shopping and employment, forcing people to commute long distances to work and shopping trips and increasing emissions in the process.

“By contrast, cities that are already dense appear to be adding population much closer to these destination, resulting in faster increases in density, less on-road travel, and flat or declining emissions per capita,” Wing said.
But there's a kicker. Or rather, there's a tipping point. Urban planners want to make cities more dense by using zoning regulations and other policies. Denser makes more efficient makes less CO2 is the thinking. But those aren't the results.
One of the study’s most important findings was that cities such as New York that were already densely populated 30 years ago saw their per capita vehicle CO2 emissions fall more quickly than other cities that have become denser more recently.

“We hypothesize that this is due to these more-dense cities already having the public transit infrastructure and more walkable, compact urban designs that makes it easier for people to move around the city with less driving,” Gately said.

Cities have had to reach a certain density—about 1,650 people per square kilometer—for vehicle emissions to fall quickly. Urban areas such as Phoenix, Denver, Houston, Atlanta, and Salt Lake City fell below that density, and each saw its per capita vehicle emissions rise. Each of those cities also saw their densities increase between 1980 and 2010, but only slightly.

Some of the densest cities with more than 1,650 people per square kilometer—New York, San Francisco, Boston, Washington, DC, and even sprawling Los Angeles—saw their per capita vehicle emissions fall or stay flat as density increased.
Yes, density leads to reduced per capita vehicle emissions but only if you are above a certain density already. Till then, you bear the costs of densification but without the CO2 benefits.

All well and good if the results of this study end up being robustly replicated. The results may be unexpected to the linear thinkers but not surprising given the track record of the field.

But there is another subtle issue here, reflected in the word choice of urban planners. Urban planners tend not just towards linear thinking but also totalitarian thinking (central planning) as well as marked ignorance of and aversion to people making free and independent choices. Urban planners usually anticipate people will act one way and are blindsided when they choose to act differently from what the planners had assumed. Free markets, complex systems and emergent order are an enigma ignored in their thinking and their modelling. It leads to odd framing of ideas as reflected in word choices.

Look at that paragraph again.
Expanding low-density cities often add population far from centers of shopping and employment, forcing people to commute long distances to work and shopping trips and increasing emissions in the process.
The clause before the comma is an empirical statement subject to being proven to be true or not. I suspect it is true.

But focus on the wording of the second clause after the comma "forcing people to commute long distances to work and shopping trips and increasing emissions in the process." In a free market with individuals exercising their freedom of decision-making, that is not what happens at all. No one is forced to do anything. They may not like the options they face (everyone wants better options) but they always have options among which to choose. One classic urban trade-off is choosing to live in the city core with all its urban amenities and advantages (restaurants, public transportation, cultural life, etc.) but in a much smaller dwelling that is more expensive and also with whatever negatives might be associated with inner city living (crime, noise, claustrophobia, health, etc.)

What is happening in the example quoted is not that people are being forced to commute long distances. They are making a decision around a complex and personal array of desires and goals: more room or less, newly constructed housing versus old housing, better schools versus worse schools, time spent commuting versus time for other activities, cost of automobile ownership versus cost of public transportation, etc.

Urban planners aren't able to compass the broad array of individual goals and trade-off calculations. Instead, they make judgments as to what might be best if everyone shared the same goals and trade-offs as those who are urban planners. In that respect, they are profoundly ignorant, arrogant and classist. They don't want others to have the freedom to make different trade-off decisions and are affronted that others do indeed make different choices than they would.

So shocked that they cannot process the concept. They suffer cognitive dissonance leading them to cast the outcomes in terms of people being forced to make different decisions than the planners think are optimal instead of, as is the case, people being free to make different choices from what planners would make in order to better maximize their life outcomes and satisfaction. Which is not to say that everyone makes good choices all the time. Of course not. But they are free to self-correct those decisions once they realize that Decision A made sense at the time but now doesn't capture their changed perspective.

The wording of this, "forcing people to commute long distances" is so revealing. I live in a city with a reviving urban core as well tens of miles of suburbs. Different people make different decisions at different points in their life based on their different priorities. The fact that that leads to ebbs and flows of greenfield development and urban renewal is an interesting phenomena. Choosing to couch all these individual decisions behind the rubric of being forced to commute hides what the urban planners wish to do which is to reduce the range of choices that people are allowed to make and force people to make the choices that urban planners, with their wretched track record of low effectiveness and unintended consequences, might themselves wish to make. A classic example of professional Gell-Mann Amnesia (described by Michael Crichton in Why Speculate?). They don't look at their own track record to judge whether there is any warrant to their current confidence in their own wisdom, an example of the Dunning-Kruger effect in action.

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