A city of homebodies? How coronavirus will change Sydney

Andrew Taylor at the Fairfax newspapers wrote a piece: A city of homebodies? How coronavirus will change Sydney. I had some quotes:

Professor of transport engineering at the University of Sydney David Levinson said public transport services may be cut because more people work at home or are reluctant to board buses and trains. “Constructing protected lanes for bikes, e-bikes, scooters is likely to be accelerated to help serve the markets that were previously served by public transport,” he said.


Levinson said consumers were also becoming more accustomed to delivery: “This returns in many ways to how life was 100 years ago, when delivery and door-to-door sales were much more common.”

His questions in bold. My fuller comments below:

– I read that Sydney and Melbourne will be particularly hard hit by the shutdown of tourism, education, entertainment and hospitality. Do you agree these industries will be the hardest hit and how will that affect Sydney?

These sectors will obviously be hard hit, I don’t know about “hardest” without doing an analysis of the full economy.

Universities will lose many international students (who pay much more in tuition and fees than domestic students and thus help cross-subsidise the education of Australians) for a year, and perhaps longer if the reputational damage or air travel barriers sustain. No one is going to pay full tuition for an online experience, and we will see a race-to-the-bottom if we think we can sell our education product as online only, diminishing the great selling point which is the location within Australia.

China already sees this as an opportunity to retain more students domestically, and other countries are competing with Australia for these students.

– How will social distancing influence urban and building design? How we shop, go out, work?

Advocates are already pushing for wider footpaths, particularly in dense urban areas, especially near bus stops where people congregate. Similarly, because of the likely reticence to use public transport and increased work at home that will emerge in the aftermath, there may be some cutbacks to public transport service. Constructing protected lanes for bikes, e-bikes, scooters, etc. is likely to be (and should be) accelerated to help serve the markets that were previously served by public transport.

– Will the pandemic accelerate moves towards online retail and the death of brick and mortar shopping?

Yes. Some stores won’t survive the crisis and won’t be replaced. Consumer shopping patterns will become even more accustomed to delivery. This returns in many ways to how life was 100 years ago, when delivery and door-to-door sales were much more common.

– Property prices are the no 1 topic in Sydney. Will they fall sufficiently to make the city more affordable? Will apartment construction slow down?

To the extent that Australia constrains immigration through additional border protection, one of the major forces driving up the prices of new construction, the international market using property ownership in Australia as a way of securing capital away from their home governments and earning points towards immigration, will be tempered. This will happen with recession in any case, but travel controls will further reduce demand pressures.

– Will the city’s population growth slow?  Will the push towards more medium and high density continue? [Dense cities such as New York seem to have been affected more by coronavirus]

As above, at least a years worth of international growth will be forgone.

– Do you think ridership on public transport will drop and be replaced by cars, bicycles or less movement around the city?

Yes, yes, yes.


A broken Reddy-Go
A broken Reddy-Go


– How will increased surveillance affect city life?

– Will it lead to increased discrimination? And calls for less migration?

The tools of surveillance are historically the tools of oppression, and it can now be automated to a degree never before possible with cameras, face identification, and everyone carrying smartphones radiating bluetooth signals. Opening up the surveillance to the general public, not just selected state-appointed guardians, the idea David Brin refers to as Sousveillance or reciprocal accountability in his book The Transparent Society is one way of addressing the problem:  Who will guard the guards themselves?

– An increased focus on hygiene will surely occur. How will this manifest itself? Past pandemics saw slum areas cleared in inner-city Sydney for example.

I hope that people will now smell cleaner air and see bluer skies as evidence that current industrial and automobile-oriented social patterns have real consequences for public health, and what life could be like if actually cared about those things. People will probably wash their hands more too.

– Despite the high death toll, the Spanish flu did not appear to have a lasting effect on people’s lives. Why do you think the coronavirus will have a greater impact?

I don’t know that it will, and I wouldn’t assume the premise. The 1957-1958 pandemic (“Asian flu”)  was quickly forgotten in popular culture despite lots of deaths globally and a sharp recession. But those million deaths (more than covid-19 probably, and a much greater share of the population) greatly affected the lives of the friends and families.

– Will manufacturing make a comeback and what affect will this have?

I think most countries will try to build and maintain larger stockpiles of general purpose medicines, PPEs, etc. There might be selected demonstrations of doing domestic manufacture which is good for photo ops and newspaper articles, but it would have to be really significant to show up in the statistics. However to the extent that the world has become extremely dependent on China-based supply chains, I think there will be efforts to spatially diversify manufacturing, particularly to other low-income countries, or anywhere when it is robotics based.

The more general trend I think is the movement away from just-in-time economy and towards a more inventory-based system to improve reliability (at the expense of short-run efficiency). I think a lot of the shortages we have seen in markets to date has been the first thrust of that. If you lack confidence the stores will be open in a week or two, because of confusing messages from public officials, you will logically stockpile.

– The federal minister for regional health told me he thought regional areas might weather the pandemic better because they have less density and industries such as agriculture and mining are not as greatly affected. What do you think?

One really significant outbreaks in the US has been in South Dakota (pretty rural as US states go)  at a meat-packing plant. Most people in “rural” areas are not lone farmers milking cows and riding tractors.

Are you sick of/from TRB

Every January, at the Washington, DC Convention Center, 15,000 people gather to exchange memes and viruses. I have attended most of the events held over the past 30 years. It seems like I get sick from most of those.

This year, I conducted a Twitter Poll to see if I was alone. The results below

Are you sick of TRB? A poll about the 2020 Washington DC Conference. Did you go this year, or not? And did you get cold or flu symptoms, or not, in the past six weeks?

16.9% TRB, ill
33.1% TRB, not ill
7.7%   Not TRB, ill
42.3% Not TRB, not ill
142 votes · Final results
A low resolution image of the logo of TRB - Transportation Research Board of the National Academies
A low resolution image of the logo of TRB – Transportation Research Board of the National Academies

The evidence from this poll of more than 142 people (coincidentally evenly split between TRB and non-TRB goers) is that you are more than twice as likely to report having gotten sick if you attended TRB (33.8%) than otherwise (15.4%). There were 71 attendees and non-attendees each in the sample, you can decide if that is sufficiently large to draw this conclusion. Obviously correlation is not causation, and there can be other causes:

  • Twitter users are hypochondriacs, easily suggestable and are faking illnesses after this was raised,
  • TRB attendees are world travelers (compared to non-attendees) and may have gotten sick elsewhere as well (which mitigates but does not absolve the Annual Meeting, as TRB is part of world travel they engage greater than the general population)
  • TRB attendees got sick from air and train travel, rather than the conference itself.

Nevertheless, I tend to believe these findings, they align with my priors and have an underlying mechanism. We can validate next year and with other conferences.

If it turns out we had coronavirus all along (for months prior to being aware of it), (people who are not dropping over dead or feeling the need to be hospitalized are not being tested in most of the world, indicating the death rate given the virus is probably much lower than reported, deaths are mostly known (though perhaps some are misclassified), cases are not) this might have been a major vector of transmission.

So in addition to the other known negative externalities of attending conferences, such as the pollution generated, we can add health effects. Do these outweigh the benefits from in-person exchange of knowledge?

The Healthiest vs. Greenest Path: Comparing the Effects of Internal and External Costs of Motor Vehicle Pollution on Route Choice 

On-road emissions, a dominant source of urban air pollution, damage human health. The ‘healthiest path’ and the ‘greenest path’ are proposed as alternative patterns of traffic route assignment to minimize the costs of pollution exposure and emission, respectively. As a proof-of-concept, the framework of a link-based emission cost analysis is built for both internal and external environmental costs and is applied to the road network in the Minneapolis – St. Paul Metropolitan Area based on the EPA MOVES and RLINE models. The healthiest and the greenest paths are skimmed for all work-trip origin-destination pairs and then aggregated into work trip flows to identify the healthier or greener roads in a comparative statics analysis. The estimates show that highways have higher emission concentrations due to higher traffic flow, on which, but that the internal and external emission costs are lower. The emission cost that commuters impose on others greatly exceeds that which they bear. In addition, the greenest path is largely consistent with the traditional shortest path which implies that highways tend to be both greener and shorter (in travel time) for commuters than surface streets. Use of the healthiest path would generate more detours, and higher travel times.
Route choice, Traffic assignment, Shortest path, Pollution, Emissions, Exposure, Intake

Measuring the transportation needs of people with developmental disabilities: A means to social inclusion (free version)

“Measuring the transportation needs of people with developmental disabilities: A means to social inclusion” is now available online. The “free” link provides free access, and is valid until May 31, 2017

Recently published:



One of the major causes of social exclusion for people with developmental disability (PDD) is the inability to access different activities due to inadequate transportation services.


This research paper identifies transportation needs, and reasons for unmet, but desired untaken trips of adults with developmental disabilities in Hennepin County, Minnesota. We hypothesize that PDD cannot make trips they want to make due to personal and neighborhood characteristics.


A survey measuring existing travel behavior and unmet transportation needs of PDD (N=114) was conducted. The survey included both demographic and attitudinal questions as well as a travel diary to record both actual and desired but untaken trips. Logistic regression analyses were conducted to determine reasons associated with their inability to make desired, but untaken trips.


Most respondents did not live independently. More than half of the surveyed population worked every day and recreation trips occurred at least once a week for about two-thirds of the population. About 46 percent were unable to make trips they needed to make. Public transit posed physical and intellectual difficulties, however the presence of public transit in neighborhoods decreased odds of not making trips. Concerns about Paratransit services were also reported.


Findings from this study can be of value to transportation engineers and planners interested in shedding light on the needs of a marginalized group that is rarely studied and have special transport needs that should be met to ensure their social inclusion in society.

“Transit Makes you Short”: On Health Impact Assessment of Transportation and the Built Environment

Recent working paper

Coefficient-p-value-sample-size (CPS) chart for Transit Share variable
Coefficient-p-value-sample-size (CPS) chart for Transit Share variable

The current research provides a test framework to understand whether and to what extent increasing public transit use and accessibility by transit affect health. To this end, the effect of transit mode share and accessibility by transit on general health, body mass index, and height are investigated, while controlling for socioeconomic, demographic, and physical activity factors. The coefficient-p-value-sample-size chart is created and effect size analysis are conducted to explore whether the transit use is practically significant. Building on the results of the analysis, we found that the transit mode share and accessibility by transit are not practically significant, and the power of large-sample misrepresents the effect of transit on public health. The results, also, highlight the importance of data and variable selection by portraying a significant correlation between transit use and height in a multivariate regression analysis. What becomes clear from this study is that in spite of the mushrooming interdisciplinary studies in the nexus of transportation and health arena, researchers often propose short- and long-term policies blindly, while failing to report the inherent explanatory power of variables. We show that there is a thin line between false positive and true negative results. From the weakness of p-values perspective, further, we strove to alert both researchers and practitioners to the dangerous pitfall deriving from the power of large- samples. Building the results on just significance and sign of the parameter of interest is worthless, unless the magnitude of effect size is carefully quantified post analysis.

Keywords: Public transit; BRFSS data; ACS data; Accessibility to jobs; p-hacking

Traffic-Related Air Pollution, Particulate Matter, and Autism

Volk et al (2012) Traffic-Related Air Pollution, Particulate Matter, and AutismAir Pollution, Particulate Matter, and Autism:

“Context  Autism is a heterogeneous disorder with genetic and environmental factors likely contributing to its origins. Examination of hazardous pollutants has suggested the importance of air toxics in the etiology of autism, yet little research has examined its association with local levels of air pollution using residence-specific exposure assignments.
Objective  To examine the relationship between traffic-related air pollution, air quality, and autism.
Design  This population-based case-control study includes data obtained from children with autism and control children with typical development who were enrolled in the Childhood Autism Risks from Genetics and the Environment study in California. The mother’s address from the birth certificate and addresses reported from a residential history questionnaire were used to estimate exposure for each trimester of pregnancy and first year of life. Traffic-related air pollution was assigned to each location using a line-source air-quality dispersion model. Regional air pollutant measures were based on the Environmental Protection Agency’s Air Quality System data. Logistic regression models compared estimated and measured pollutant levels for children with autism and for control children with typical development.
Setting  Case-control study from California.
Participants  A total of 279 children with autism and a total of 245 control children with typical development.
Main Outcome Measures  Crude and multivariable adjusted odds ratios (AORs) for autism.
Results  Children with autism were more likely to live at residences that had the highest quartile of exposure to traffic-related air pollution, during gestation (AOR, 1.98 [95% CI, 1.20-3.31]) and during the first year of life (AOR, 3.10 [95% CI, 1.76-5.57]), compared with control children. Regional exposure measures of nitrogen dioxide and particulate matter less than 2.5 and 10 μm in diameter (PM2.5 and PM10) were also associated with autism during gestation (exposure to nitrogen dioxide: AOR, 1.81 [95% CI, 1.37-3.09]; exposure to PM2.5: AOR, 2.08 [95% CI, 1.93-2.25]; exposure to PM10: AOR, 2.17 [95% CI, 1.49-3.16) and during the first year of life (exposure to nitrogen dioxide: AOR, 2.06 [95% CI, 1.37-3.09]; exposure to PM2.5: AOR, 2.12 [95% CI, 1.45-3.10]; exposure to PM10: AOR, 2.14 [95% CI, 1.46-3.12]). All regional pollutant estimates were scaled to twice the standard deviation of the distribution for all pregnancy estimates.
Conclusions  Exposure to traffic-related air pollution, nitrogen dioxide, PM2.5, and PM10 during pregnancy and during the first year of life was associated with autism. Further epidemiological and toxicological examinations of likely biological pathways will help determine whether these associations are causal.”

In general pollution has been going down in the US, and autism diagnosis has been going up. Some of that may be diagnosis issues (though the previously linked article suggests not). However, there is an interesting point, in the Volk article: “In addition, ultrafine particles (PM0.1) may penetrate cellular membranes.” As we filter larger and larger pollutants from the tailpipe, we may be making more small pollutants (One way to reduce measurable pollution particles is to make them smaller, so they are no longer measured). For instance the as wikipedia says about the Diesel Particulate Filter “maintenance free DPF break larger particles into smaller ones.”

Breakfast cereal, Utopia, and Eugenics

There is a strange connection between breakfast cereals, utopia, and eugenics.
Wikipedia writes about Ralstonism, which begot the Ralston Purina company, Chex cereal (now owned by General Mills), and whose successor company Ralcorp owns Post Cereal :

“Ralstonism was a minor social movement in 19th century USA. It claimed about 800,000 followers. Ralstonism was the brainchild of Webster Edgerly (1852 – 1926). In Edgerly’s words, “Ralstonism is the grandest movement that man is capable of establishing”. Ralstonism began as the Ralston Health Club, which published Edgerly’s writings. It was a hierarchical organization where members were ranked according to the number of “degrees” they had, which ranged from 0 to 100. Members advanced five degrees at a time, and each Ralston book that a member purchased counted as five degrees. Although Edgerly claimed in the 1900 edition of The Book of General Membership of the Ralston Health Club that the letters for the word RALSTON came from Regime, Activity, Light, Strength, Temperation, Oxygen and Nature, earlier editions of the same book are credited to Everett Ralston, a pseudonym of Edgerly, with the implication that Ralstonism is named after this fictitious person. Edgerly saw his followers as the founding members of a new race, based on Caucasians, and free from “impurities”. He advocated the castration of all “anti-racial” (non-Caucasian) males at birth.”

John Harvey Kellogg

“… was an American medical doctor in Battle Creek, Michigan, who ran a sanitarium using holistic methods, with a particular focus on nutrition, enemas and exercise. Kellogg was an advocate of vegetarianism and is best known for the invention of the corn flakes breakfast cereal with his brother, Will Keith Kellogg He led in the establishment of the American Medical Missionary College. The College, founded in 1895, operated until 1910 when it merged with Illinois State University.”

He founded the Battle Creek Sanitarium

“Battle Creek Sanitarium was world renowned and became the ‘in’ place for the rich and famous to seek their lost health, to listen to health lectures and to learn and practice the principles of a healthy lifestyle”. “Kellogg was outspoken on his beliefs on race and segregation, though he himself adopted a number of black children. In 1906, together with Irving Fisher and Charles Davenport, Kellogg founded the Race Betterment Foundation, which became a major center of the new eugenics movement in America. Kellogg was in favor of racial segregation and believed that immigrants and non-whites would damage the gene pool.”

Similarly C.W. Post

“Visited the Battle Creek Sanitarium operated by John Harvey Kellogg for his failing health. He was inspired to start his own cereal company based on the products used there.”

Now for the tenuous transportation angle: Among the visitors to the Battle Creek Sanitarium were Richard Halliburton

” Best known today for having swum the length of the Panama Canal and paying the lowest toll in its history—thirty-six cents—Halliburton was headline news for most of his brief career. His final and fatal adventure, an attempt to sail a Chinese junk, the Sea Dragon, across the Pacific Ocean from Hong Kong to the Golden Gate International Exposition in San Francisco, made him legendary.”,

Amelia Earhart and Henry Ford.
Chew on that as you eat your Wheaties (which as a General Mills product seems to be free of the Eugenics craze of the turn of the last century, and depicted Jesse Owens on its box in 1936, breaking the color barrier quite early).

Long commutes cause obesity, neck pain, loneliness, divorce, stress, and insomnia.

Annie Lowrey in Slate Magazine: Long commutes cause obesity, neck pain, loneliness, divorce, stress, and insomnia. : “This week, researchers at Umea University in Sweden released a startling finding: Couples in which one partner commutes for longer than 45 minutes are 40 percent likelier to divorce.”

(Via Marginal Revolution.)