Transportist: 17 Top Posts of 2021

The most popular Transportist posts from 2021 were not written in 2021. On Misery Loves Company from 2017 has taken a life of its own, for some reason. (punchline: miserable people don’t want company, misery itself does, which is why it spreads).

But the aim of this post is to promote stuff published this year, so these were the most popular (excluding of course, this post itself, for which we don’t yet have statistics). Traditional posts, as opposed to links to other publications (papers, student theses, videos, etc.) are declining as my time is finite and more effort goes to the newsletter. But in case you missed any of the below: happy reading, and may 2022 be better.

What if it’s only once a week?
Notes from a Prison Colony
Urban access across the globe: an international comparison of different transport modes
Towards the 30-minute city — how Australians’ commutes compare with cities overseas
Access as a performance indicator in a work-from-home world
Observations of Arncliffe
Applications of Access
Optimum Stop Spacing for Accessibility
Road traffic almost back to pre-COVID levels as commuters shun public transport | Sydney Morning Herald
Longing to Travel: Commute Appreciation during COVID-19
Accessibility-oriented planning: Why and how to make the switch
The Ensemble Approach to Forecasting: A Review and Synthesis
Auto buybacks: Cash for ICE — Accelerating the Transition to EVs (and AVs while we are at it)
Job and Worker Density and Transit Network Dynamics
The Economics of Findings
Elements of Access — Now with Video

The Evolution and Prediction of Bus Transportation in Greater Sydney Using Econometric Models

Recently published:


This thesis utilises econometric methods in the context of bus network service prediction utilising the Greater Sydney bus network between 1926 and 2013. Using historical bus GTFS data, the method with which this is transformed to find the level of service per link, as given by the Open Street Maps network is also shown. Weighted spatial variables are described where the strength of the spatial relationship is given by a region-level correlation matrix, also described within this work. The lagged service variable is found to define to a high degree the number of services experienced on a link in any given year, with the addition of complementary and competing spatial variables improving the model fit marginally or leaving it unchanged. As expected, lagged complementary variables have positive correlations with to service levels in the proceed- ing year, while competing links show the opposite relationship. The lagged service level model for the entire Greater Sydney region is further compared against the region-level spatial model, showing that only few circumstances offer a superior performance of regional models to the aggregated.

Bus Network Frequency, Sydney, 2013

Creating a Historical Database for Roads in Greater Sydney using Map Digitisation

Recently published:


The aim of this thesis is to create a historical database for roads in Greater Sydney using map digitisation. The database was constructed to label the status of road in Sydney at a certain time by nominating their opening date, and if applicable, their closing date. The project was completed in the QGIS working environment, an open-sourced program that allows for map digitisation to be completed. A method was developed for map digitisation that can be used to extract spatial data from historical maps and place them in a collective vector layer. The method considers extensive georeferencing of the maps, as well as editing and cleaning the maps through raster and vector analysis. Preferred methods for map digitisation used in the project were identified. For a considerable area of Sydney, in which approximately 52000 road links were included, almost half of the links were identified with an open date by the start of the twentieth century. A further half of these links were confined to opening within a thirty-year period. The progressive change in open links, the length of the network, the area of the network surveyed and the number of intersections open was also reviewed with time. The project has established a strong foundation for a historical road database for Sydney. It has also outlined methods and procedures that can be followed to progress the database further.

Growth of the Sydney Street network. Source: Turner, Hamish (2021)

Network Econometrics and the Evolution of Transport Systems

Recently Published


This thesis systematically develops a network correlation matrix that explicitly distinguishes competitive and complementary link pairs in transportation networks. Embedding the matrix in network econometric analysis, this thesis consolidates that incorporating representative spatial information with a network perspective is capable of improving the performance of traffic forecasting models. The method is validated in the context of a real-world transport system rather than within simulated settings adopted by previous research. An Autoregressive-Distributed Lag (ARDL) model is specified, and reveals that the combination of correlation strength and magnitude of lagged flow change on correlated links is an significant predictor of future traffic flow. This thesis innovatively extends network econometric methods, previously exclusively used for traffic flow forecasting, to the domain of network structure prediction by specifying a logit model. It finds that complementary and competitive links play distinct roles in shaping the network structure. If positively correlated, a link is more likely to undergo the same structural change influential links underwent previously where the influence is measured by a combination of correlation strength and link importance, reflected by historical flow level. Additionally, this thesis establishes a digitized database of the Sydney tramway system, providing a complete set of data for more research.

Trams running through Railway Square, 1920s

Streetcars Across America: An Analysis of the Growth and Decline of Electric Urban Railways in the United States from Directory Data

Recently published


This thesis report describes the extraction of records from the McGraw Electric Railway Manuals to rectify the lack of documentation around streetcar systems through technological means, and discusses the appropriateness of using technology to analyse century-old directories. The extracted records are analysed on a metropolitan, state and national level, and fitted to logarithmic S-curve models to describe their growth and decline.

Transportist: December 2021


Now available for download: Applications of Access.

Applications of Access edited by David Levinson and Alireza Ermagun


Our open access book Applications of Access, edited by David Levinson and Alireza Ermagun has launched!

Applications of Access was inspired by our belief that planning should reach beyond mobility and incorporate all intricacies of reaching your destination. We set out to publish a book examining topics such as (1) Equity and social justice, (2) Resilience and crisis, (3) Active transport, (4) Public transport, (5) Auto travel, (6) System performance, and (7) Project evaluation.

But this book is not intended to simply be a “how to” manual, but rather to inspire researchers, practitioners, and policymakers to spark a broader array of research and practice in the nexus of transport access.  
This was a labor of love that included the work of many of our colleagues and thought leaders in the transport community. We are thrilled to finally be able to share our work with you, and we hope to embolden our greater transport community to examine access through the many lenses that impact our daily commutes and quality of life.

Table of Contents

1 An Introduction to Applications of Access
Alireza Ermagun and David Levinson 15

2 Fostering Social Equity and Inclusion
Pâmmela Santos and Geneviève Boisjoly 23

3 Justice, Exclusion, and Equity: An Analysis of 48 US Metropolitan Areas
Chelsey Palmateer and David Levinson 45

4 Disparity of Access: Variations in Transit Service by Race, Ethnicity, Income, and Auto Availability
Elisa Borowski, Alireza Ermagun, and David Levinson 69

5 Access During COVID
James DeWeese, Kevin Manaugh, and Ahmed El-Geneidy 87

6 Access to Shelters
Mahyar Ghorbanzadeh, Kyusik Kim, Eren Erman Ozguven, and Mark Horner 105

7 Access and Centrality-Based Estimation of Urban Pedestrian Activity
Brendan Murphy, Andrew Owen, and David Levinson 117

8 Which Station? Access Trips and Bikeshare Route and Station Choice
Jessica Schoner and David Levinson 133

9 Cargo Bikesharing as a Last-mile Connector
David Duran-Rodas, Aaron Nichols, Benjamin Büttner 149

10 Spatio-temporal Transit Access to Food Stores
Xiaohuan Zeng, Ying Song, and Na Chen 165

11 Multi-destination Access
Andrew Guthrie and Yingling Fan 193

12 Non-work Vehicle Trip Generation from Multi- week In-vehicle GPS Data
Arthur Huang and David Levinson 217

13 Job Access and Spatial Equity of a Toll Road
I Gusti Ayu Andani, Lissy La Paix, Shanty Rachmat, Ibnu Syabri, and Karst Geurs 239

14 Access and Transit System Performance
Alireza Ermagun and David Levinson 261

15 Intraurban Access and Agglomeration
Michael Iacono, Jason Cao, Mengying Cui, and David Levinson 277

16 Transit Access Performance Across Chicago
Fatemeh Janatabadi, Nazanin Tajik, and Alireza Ermagun 291

17 Interactive Access for Integrated Planning
Anson Stewart and Andrew Byrd 307

18 The Role of Transit Service Area Definition for Access-based Evaluation
Chelsey Palmateer, Alireza Ermagun, Andrew Owen, and David Levinson 327

19 Access-based Evaluation of Transit-Oriented Developments
Chelsey Palmateer, Andrew Owen, and Alireza Ermagun 347

20 Physical and Virtual Access
Tanhua Jin, Long Cheng, and Frank Witlox 363

Editors and Contributors 377

Bibliography 387


  • 424 Pages
  • Publisher: Network Design Lab


Geo-Engineering Wars

“It’s 2040, and while annual carbon emissions have been dropping for decades, planet Earth remains nowhere near net zero, and CO2 continues to accumulate in the atmosphere. Global institutions have failed (again) to resolve the issue.  Temperatures are rising. Glaciers are melting. The permafrost is a lot less perma. Sea-levels are rising. Fires are increasing. Tensions are rising.

This affects some places more than others, and those governments take it upon themselves to mitigate the effects. The once fringe field of geo-engineering, attempting to control the earth’s climate, has come to the fore. From relatively innocuous technologies like carbon capture and afforestation, to more radical attempts at blocking the sun and adding iron to the oceans are leaving the simulator and being tested in the field.”

That was a blog post I started a couple of years ago and never finished. Two new novels have finished it (and I have finished them). Kim Stanley Robinson’s “Ministry for the Future” and Neal Stephenson’s “Termination Shock” both deal with Climate Change, Geo-Engineering and the conflicts around them. Just as the cyberpunk novels of the 1980s predicted our era surprisingly presciently, I believe the new climate novels will help lay the groundwork for openly discussing the still verboten topic of geo-engineering once we realise we are going to have unacceptable climate if we rely on public policy, emissions reduction, and technology substitutions alone.

Speaking of which, I did the following Twitter poll: 

Considering global change and the desire to stay below 1.5C temperature rise from the baseline. Which of the following will ensure that. Tech includes substitutions (EVs, Solar, etc.) and Carbon Capture and Storage etc. of various types:

  • Technology changes 11.1%
  • Behavioural changes 14.8%
  • Technology + Behaviour 63%
  • Nothing 11.1%

More on: How to value transport projects

Following up on the October newsletter:


In your newsletter today you seem to argue that land value uplift is a reliable reflection of access, so that access can be measured either directly or through the value the real estate market places on it.

I was puzzled about this, because the real estate market clearly has all the stupidity of any investment bubble. US streetcars increased land value even when they provided no access, for no other reason than that access-ignorant investors believed that they did.

Do you believe, then, that land value tends to reflect access in the longer run? This would require believing that the effects of marketing are temporary but that access is a permanent value and thus tends to count for more after the marketing wears off. That’s my view, but it’s more an abstract philosophical assumption than something I could support with data.

This probably deserves textbook length treatment, more than a newsletter in any case, but my view in brief:

Land values are a good measure of relative value in the short and long run, better in the long run than the short run if only because the number of transactions is larger and the marginal value of the particular buyers at a given time will lead to speculative excesses (optimism and pessimism) and when averaged over time will more closely approximate the average value of all prospective land owners. 

Value is determined by people (the subjects), not by the observer (the modeler), and their weights on access to different types of things varies over time (yesterday it was jobs, today beaches matter more, tomorrow it will be a particular public school, the day after that it will be access to snooty neighbours). The land market summarises their willingness to pay to access to everything, though the modeller can at best capture only a limited amount of that (concrete things like jobs and beaches, assuming they don’t change). So our model of 

land value = f ( access)

Won’t have an $R^2$ of 1, but it is better than most people would think (we routinely can get $R^2$ of 0.7 in these kinds of models on individual properties with access and all the typical property attributes, it might be better if we aggregate to neighbourhood level land values).

The key point though isn’t the absolute but the relative value.

The government will dial in the amount of revenue they want to receive, and allocate taxes proportionate to land value (i.e. proportionate to measurable access), and that would be far superior to anything we are doing now.

Two questions:

* When you talk about relative land value are you talking about delta of land value? Or value of a parcel relative to other parcels of the same size and with other differences controlled for? I’m guessing the latter. So the land value variable is a ratio (or absolute difference?) to some baseline rather than a \$ amount?

* In your formula land value = f (access), there are, as you say, many kinds of access (both destinations and travel time thresholds) that could be calculated. Do you achieve this high r-squared by querying the market about how different kinds of access are weighted, and if so how is this not circular? If not, how do you define this variable?

I meant relative across places. The absolute land value is just an arbitrary price (how much people value land compared to travel or tourism etc.), and sometimes real estate rises faster than the economy as a whole (or changes in access dictate) and sometimes slower, and depends on things like tax policy and interest rates. 

The proportion of total (say metropolitan) real estate value associated with each place is largely proportional to its access to things. I recognise what things people value is in a large sense arbitrary too (cafes vs brothels vs stadiums etc.), compared with other places in the same metropolitan area, but I suspect it is more stable in the long run, with slower changes over time as preferences and technology change, for instance we would expect the value of access to office buildings dropping over time as work from home becomes more common. 

We have used different kinds of access. It turns out transit access (30 or 45 minutes) seems to be the best predictor in Sydney (explain the most variation) if you have only one measure. We think this is because auto access is fairly invariant across the region, while transit access concentrates pretty highly. I have attached a working paper (currently under review, not for citation or sharing). 

The statistical issue with having lots of access measures in a single regression is autocorrelation … access to jobs is not really that independent of access to shops or access to restaurants etc, and access by bike is similar to access by auto, etc.

The idea here is ensemble models, this paper is a just a starting point. Different models are estimated with different clusters of variables and different statistical methods. The model predictions are combined, and this improves the prediction compared with any single model.


Regarding the below, do you think that the same principles apply to freight projects in regional/rural areas? And if yes, do you think they would have a significant impact on their valuations?

Yes in principle. It may be harder to capture the land value benefits or determine the accessibility changes associated with industrial or mining or agricultural land with a freight-oriented highway or rail project (though I haven’t really tried). But the general idea of taxing land should capture an appropriate fraction of the benefits that arise.

I don’t know the NSW context well enough, but in the US I also tend to think that today’s freight projects (compared with 60 years ago) don’t add much value. Widening (i.e duplicating) an uncongested 2 lane to a very uncongested 4 lane road adds nearly zero time savings value for freight (a little bit more for non-freight traffic which can overtake the slower moving freight), and may or may not make things safer, depending. A new bridge or tunnel is likely to be more significant. 

Adam Smith talked exactly about the value of agricultural land rising after turnpikes and canals were built in the 1700s.


I would add that improvements to more affordable and slower modes, and the disadvantaged groups that rely on them, help achieve social equity goals more than comparable size improvements to expensive and faster modes.

I would also add that the analysis should consider indirect and down-stream impacts. For example, a highway expansion assumes that beneficiaries will use an automobile, and that somebody will provide parking at their destinations, costs that are reduced or eliminated if the same travellers arrive by biking, ridesharing or public transit. Project cost comparisons often overlook those impacts, which further exaggerates highway expansion benefits.

More of a comment than a question, but indeed they do.

Types of Problems

  • Via Kevin Kelly: Class 1 / Class 2 Problems “There are two classes of problems caused by new technology. Class 1 problems are due to it not working perfectly. Class 2 problems are due to it working perfectly.” Apply this to AVs.

What Remains Unknown in Transport and Land Use Research

I asked on Twitter:

Q: What do we *not* know about transport and land use interaction, that is knowable?  I don’t meant the third digit of precision on some relationship, but more fundamental things?  What are the big unanswered questions?

Some responses below. I am not sure I agree with these. I am not sure I have a strong opinion on what are the big unanswered questions? Maybe we know everything and we just need to put it in practice.

Patrick Zilliacus

act of NIMBYism (not in my back yard), PIITBYism (put it in their back yard), PIBBY (place in blacks’ back yard), BANANA (build absolutely nothing anywhere near anything) and CAVE (citizens against virtually everything) is worthy of more and better research.

Juste Raimbault

A general theory and models of co-evolution of land-use and transport: circular causal relationships seems overlooked – these occur on multiple temporal and spatial scales. When does transport drives land-use, when does land-use drives network development, when do both strongly interact and are in circular causality? Also the role of governance in transport network growth-we did some preliminary work on that here

David King

I think a lot of what we know is based on a strong transport/land use interaction. If that relationship is weakening, then much of what we do know may not matter as much.

We also know less about transport/land use with many transport providers/price setters (e.g. fees/tolls).

Jago Dodson

I would argue we don’t know the isolated effect of the automobile on land-use and transport. It’s almost impossible to fully exclude as a variable among the historical development of urban structure. What would a zero-car contemporary city be like? We can guess, but not know.

James Milne

The full relationship between residential and workplace density vs % active and public transport use vs number of small businesses in a given location. Or in other words, the “formula” for a 15minute city.

Vic Walks

Governments very interested in job creation through construction, but seems almost no research on job creation in construction of walking and cycling infrastructure

Josephine Roper

How important it is or is not for wellbeing and happiness for people to live close to people they know. Because this has implications when we assume that people will or should efficiently relocate to be near the destinations (land use) they need to access

Tamara Kerzhner

Agreed – we underconsider social and personal life travel. Frame it as “access to social capital” and “mobility of household reproduction” if it gets it past the economists.

Mikael Valstead

The full societal cost of driving a car (health, noise, inactivity, CO2 and other GHGs, micro plastic from tires, destruction of housing and green areas, congestion, etc.)

Peter Rickwood

The political economy of land-use/transport. Government action is absent or poorly understood in transport/land-use theory and modelling, but in practice very important (zoning, infrastructure spend, value-capture & congestion charges, user fee structure, etc).

Soren Have

[rewritten] Why does the amount of land devoted to transport purposes keeps growing.

John Macilree

That land use for airports involves a much larger area than the physical confines of the airport property when noise and glide slope considerations are taken into account. That land developers see related vacant land and will try to use political pressure to exploit this land.

Recent Research by Others

  • Ryerson, Megan S., Carrie S. Long, Joshua H. Davidson, and Camille M. Boggan. “New Rules for Old Roads.” Issues in Science and Technology 37, no. 2 (Winter 2021).“Collecting and analyzing biometric data from nonmotorists would shift the way safety is measured by the entire transportation and public health community—with implications for infrastructure policy and design.”