Month: August 2017
Indifference Bands for Route Switching
Printed, (after more than a year in “online first” purgatory) and now available for FREE Viewing.
- Di, Xuan, Henry Liu, Shanjiang Zhu, and David Levinson (2017) Indifference Bands for Route Switching. Transportation. 44:1169–1194 [doi] [full-text view only]
Abstract: The replacement I-35W bridge in Minneapolis saw less traffic than the original bridge though it provided substantial travel time saving for many travelers. This observation cannot be explained by the classical route choice assumption that travelers always take the shortest path. Accordingly, a boundedly rational route switching model is proposed assuming that travelers will not switch to the new bridge unless travel time saving goes beyond a threshold or “indifference band”. To validate the boundedly rational route switching assumption, route choices of 78 subjects from a GPS travel behavior study were analyzed before and after the addition of the new I-35W bridge. Indifference bands are estimated for both commuters who were previously bridge users and those who never had the experience of using the old bridge. This study offers the first empirical estimation of bounded rationality parameters from GPS data and provides guidelines for traffic assignment.
Bounded rationality, Indifference band, Empirical estimation, GPS study, Route Choice
Roderick Distinguished Lecture
Roderick Distinguished Lecture
Thursday 31 August 2017
Join us on Thursday 31 August 2017 for the second Roderick Distinguished Lecture for 2017 featuring the Sydney Metro Program Director for Transport for NSW, Mr Rodd Staples. presenting an insight into the Sydney Metro project, his path to such a role and the opportunities available for civil and other engineering graduates to help deliver the transport infrastructure required of a modern city.
Sydney Metro is Australia’s biggest public transport project, with 31stations and 66km of new metro rail.
This project comes at a time of the launching of the Transportation Engineering major within the Faculty of Engineering & IT, which provides students with the opportunity to embrace the mathematical and engineering methods required to plan, design, operate and manage the infrastructure necessary to achieve safe, economical and environmentally sustainable movement of people and goods.
Professor David Levinson who has recently joined the School to lead the implementation of this new major, sees it as an exciting time to be in a city where there is currently a generation’s worth of major transport infrastructure projects occurring simultaneously.
Rodd has almost twenty years experience in transport and infrastructure, across both government & private sectors. With tertiary qualifications in civil engineering & finance, Rodd has worked across a mix of senior executive, project management & technical leadership roles with a core career focus on transport project planning, development and delivery.
“The opportunity to work on a city-transforming project with such a dedicated team is a privilege and one that I am very proud of,” Rodd says.
“We are delivering a new metro system with the customer as its focus which will help transform public transport in Sydney.”
Thursday 31 August 2017
Open from 5:00 for 5:30pm start, followed by refreshments and networking from 6:30pm
PNR Lecture Theatre No 2, Faculty of Engineering & IT, University of Sydney
This event is free but please CLICK HERE to register or contact Malcolm Boyd (see details overleaf)
The Roderick Distinguished Lecture Series
The Roderick Distinguished Lecture Series brings the leaders of industry and government to the University to present to the civil engineers of tomorrow the challenges and opportunities which they and their organisations face and the role that civil engineering plays in their work environment
The Roderick Lectures are an initiative of the Council for Civil Engineering Sydney, an industry advisory group formed to assist the School of Civil Engineering to deliver world-class education and research through an inclusive program of engagement between industry and academia at all levels.
The Roderick Lectures are promoted widely to the students as well as the industry network of the School of Civil Engineering
The Roderick Lecture series acknowledges Professor Jack William Roderick who, as Head of School from 1951 to 1978, initiated programs of engagement with industry to build and to augment the teaching and research programs of the School through the Graduates Association and the Civil Engineering Foundation.
For more information
Malcolm Boyd| Executive Officer | Council for Civil Engineering Sydney
T 0412 797 479 | E firstname.lastname@example.org
Specialists say parking shortfalls for Hornsby and Ku-ring-gai commuters will require wide range of solutions
I was interviewed by Jake McCallum of the Hornsby Advocate (part of the Telegraph family) for the article: “Specialists say parking shortfalls for Hornsby and Ku-ring-gai commuters will require wide range of solutions” My quotes below:
University of Sydney Civil Engineering specialist, Professor David Levinson said “while having fast, direct, frequent, and reliable public transport service is important, being able to get to that service is critical”.
“Governments shouldn’t shy away from cheap, effective forms of transport to train stations,” he said.
Mr Levinson said he was shocked at Ku-ring-gai Council’s estimates of costs to cure parking shortfalls.
“Rather than focusing on plans that see $200 million used to fund the development of 2600 parking space, we should be looking into the feasibility of large scale bicycle racks as a form of commuter parking,” Prof Levinson said. “It [parking] is not the best use of public capital.”
Hornsby Council and Hornsby state Liberal MP Matt Kean did not make submissions to the parliamentary inquiry. However, Mr Kean said he was proud to have delivered 42 extra car spaces at Asquith station.
“My focus now is doubling capacity of the carpark at Hornsby station,” he said.
This follows up on my Parliamentary submission on Commuter Car Parking.
Measuring Winners and Losers from the new I-35W Mississippi River Bridge | FREE Viewing
Finally printed, (after more than a year in “online first” purgatory presumably accumulating citations so the journal can juice it’s impact factor) now available for FREE Viewing, but not downloading, thanks to the new initiative below. While not perfect, this seems a reasonable step on the path towards full open-access.
- Zhu, Shanjiang, David Levinson, and Henry Liu (2017) Measuring Winners and Losers from the new I-35W Mississippi River Bridge. Transportation. 44:905–918 [doi] [full-text view only]
Congratulations on publishing “Measuring winners and losers from the new I-35W Mississippi River Bridge” in Transportation. As part of the Springer Nature SharedIt initiative, you can now publicly share a full-text view-only version of your paper by using the link below. If you have selected an Open Access option for your paper, or where an individual can view content via a personal or institutional subscription, recipients of the link will also be able to download and print the PDF. All readers of your article via the shared link will also be able to use Enhanced PDF features such as annotation tools, one-click supplements, citation file exports and article metrics.
We encourage you to forward this link to your co-authors, as sharing your paper is a great way to improve the visibility of your work. There are no restrictions on the number of people you may share this link with, how many times they can view the linked article or where you can post the link online.
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Kristin Carlson: Accessibility Impacts of Bus Access to Managed Lanes
Congratulations to Kristin Carlson for successfully defending her MS Thesis: “Accessibility Impacts of Bus Access to Managed Lanes” at the University of Minnesota Department of Civil, Environmental, and Geo- Engineering on August 22, 2017. The thesis will be made publicly available soon.
This research introduces a method to measure changes in transit accessibility resulting from adjustments in bus-highway interactions. Operational differences between general purpose (GP) and managed lanes (ML) are measured using average travel time. Changes to transit travel time are systematically introduced to General Transit Feed Specification (GTFS) data through the use of the StopTimesEditor computer program developed for the purpose of this analysis. The methodology is tested on two express bus routes in the Minneapolis – St. Paul region (Twin Cities). The change in operating speed along portions of the selected transit routes is translated to changes in the job accessibility of the surrounding communities. The percent change in the worker-weighted average job accessibility for the area surrounding the transit routes and for the entire metropolitan region are 12% and 0.25% respectively. The methods introduced in this study can be used to evaluate the accessibility impacts of different highway operating environments for buses, or estimate the accessibility outcomes of different bus-highways scenarios.
Dr. Jessica Schoner: Mutually Reinforcing Relationships Between Bicycling Infrastructure
Congratulations to soon-to-be Dr. Jessica Schoner for successfully defending her dissertation: ‘Mutually Reinforcing Relationships Between Bicycling Infrastructure’ before a standing room only crowd at the University of Minnesota campus on 21 August 2017.
Researchers have long sought evidence about whether dedicated bicycling infrastructure induces people to cycle, based on a supply-driven assumption that providing infrastructure causes the behavior change. However, supply inducing demand is only one of four theoretical relationships between bicycling and infrastructure. The aims of this research are twofold:
- Develop a theoretical framework to identify and evaluate all of the possible relation- ships between bicycling and infrastructure and describe how these factors reinforce one another to shape diffusion of bicycling and infrastructure in cities; and
- Develop and execute a research plan to empirically model selected hypotheses within the theoretical framework.
The empirical portion of the dissertation tests the hypotheses that (1) bicycling infrastructure supply induces bicycling demand, and (2) bicycling demand induces additional demand. The research uses a series of cross-sectional tests at multiple points in time as well as lagged variable models to add a layer of temporal precedence to our otherwise cross-sectional understanding of associations between bicycling and infrastructure. The findings show persistent associations between infrastructure and bicycling over time, across geographies, and at both the individual and aggregate level. The association between bicycling and additional bicycling holds over time at the individual household level and for bike share membership. However, the tests failed to find evidence of bike share stations and activity affecting general population cycling rates.
This dissertation provides a roadmap for future research into feedback loops between bicycling and infrastructure. It additionally provides practitioners with guidance on both the strengths and limitations of both infrastructure provision and socially-focused bicycling initiatives.
Like most bicycling research, this dissertation is limited by the quality of data available for both bicycling behavior and infrastructure supply. Neither the data nor the tests performed are rigorous enough to infer causality; instead, the findings add strength and nuance to the existing body of literature.
Papers related to the dissertation are available at:
- Schoner, Jessica and David Levinson (2014) The Missing Link: Bicycle Infrastructure Networks and Ridership in 74 US Cities. Transportation 41(6) 1187-1204. [doi]
- Schoner, Jessica, Greg Lindsey, and David Levinson (2016) Is Bikesharing Contagious? Modeling its effects on System Membership and General Population Cycling. Transportation Research Record: Journal of the Transportation Research Board. 2587 pp. 125-132. [doi]
- Schoner, J., & Lindsey, G. (2015). Differences Between Walking and Bicycling over Time: Implications for Performance Management. Transportation Research Record: Journal of the Transportation Research Board, (2519), 116-127. [doi]
- Schoner, J, Lindsey, G., and Levinson, D. (2014) Factors Associated with the Gender Gap in Bicycling Over Time. Presented at Transportation Research Board Annual Meeting 2015.
The final dissertation will be posted online soon.
As every good dissertation should, it raises as many questions as it answers, and if you are looking for a topic, there are strong research opportunities available to test Hypotheses 2 and 4 on the effect of bicycling demand on infrastructure, and infrastructure momentum. There are also opportunities to examine the new stationless bike sharing systems that are emerging in China (and Australia, and elsewhere) regarding Hypothesis 3 and social diffusion.
Some other bicycling research led by the newly minted Dr. Schoner includes:
- Nice Ride Minnesota Program Evaluation. [Twin Cities] [Bemidji]. Blue Cross/Blue Shield of Minnesota.
- Travel Behavior Over Time. Minnesota Department of Transportation/Metropolitan Council.
- NiceStations: Optimally Locating NiceRide Minnesota Bike Share Stations. Center for Transportation Studies.
- Schoner, J. and D. Levinson (2013) Which Station? Access Trips and Bike Share Route Choice. Presented at Transportation Research Board Annual Meeting 2014.
The paper from her MS Thesis is available here:
- Schoner, Jessica, Xinyu (Jason) Cao, and David Levinson (2015) Catalysts And Magnets: Built Environment Effects On Bicycle Commuting. Journal of Transport Geography 47 100–108. [doi]
The forgotten station |Honi Soit
The transportist gets a shout out in The forgotten station by Simon Coleman in Honi Soit, the University of Sydney newspaper. The article concerns Redfern station, which we talked about earlier in Sydney train stations need two exits. An excerpt below:
40 per cent of USyd students use the station to commute to campus, and the University expects the student population to increase by 26,000 to 75,000 in the next two decades. Director of campus infrastructure services Greg Robinson has labeled Redfern Station “inadequate” while lobbying the state government unsuccessfully for light rail and metro, according to the Sydney Morning Herald. In 2015 the University lost out to Waterloo for a new metro station as part of the second harbour crossing, and the proposed West Metro is unlikely to go anywhere near the University. Three years prior, in 2012 UNSW prevailed over USyd for a light rail link. More recently, the state government has canceled light rail planning for Parramatta Road (and given Labor’s lack of support) it is unlikely to happen anytime soon. Given the absence of planned alternative transport options for the University, Redfern Station looks set to become increasingly important.
Previous government studies (obtained by the RedWatch community organisation under freedom of information laws) have shown that Redfern’s capacity and accessibility could be increased while preserving its heritage. The original entrances on Lawson Street could be closed, and a modern concourse with two staircases and lifts to every platform (removing the bottlenecks of the old cramped stairs) built at the opposite southern end of the platforms. The new concourse would have an eastern entrance at Gibbons Park near the apartment towers, and a western entrance at a pedestrianised Little Eveleigh Street or Ivy Lane. This western entrance would provide a direct walk to campus and pedestrian access far less cramped than Lawson Street. As University of Sydney Professor of Transport Engineering David Levinson notes on the Transportist website, the western entrance would reduce backtracking and save at least a few minutes of walking to campus.
I would hope that not merely would there be a new “southern” entrance to Redfern, but that the “northern” entrance would be retained.
9 Barriers to Walking in Sydney
I am a pedestrian in Sydney, living in a car-less household, so I have had a few months experience in the pedestrian environment. As nice as walking in Sydney is, walking in Sydney should be nicer. For a city with such high densities of people and shops, such a large number of parks, doors on the street, and gorgeous weather, and such terrible internet service driving people from their homes, walking should be the dominant mode. Yet there are barriers to living the motor-free lifestyle here (and undoubtedly elsewhere). Some that come to mind.
T-Intersections Intentionally missing crosswalk markings (and pedestrian signals) are quite common, especially at T-intersections, where pedestrians might only have markings and a signal on one side. While this undoubtedly makes cars go faster (the presumed purpose for this), it makes the walker’s life more miserable, reducing choice and potentially adding travel time. For longer distance trips, backtracking can be avoided by crossing upstream where the signal is available. For short distance trips, this is inefficient. The largest T-intersection I have encountered where this is an issue is City Road at Broadway, where to get from the east side of City Road to the north side of Broadway (which houses a nice shopping mall) requires crossing both streets instead of just one.
- Fences. Walking midblock is strongly discouraged on some roads. Presumably for safety and for traffic flow, but still creating a chaffingly regulated environment for the pedestrian who wants to cross the shopping street.
OBEY Pedestrians must obey traffic signals or risk getting run over. While almost all of the Pedestrian Actuation (Beg) Buttons work, the phasing of traffic signals is so chaotic as to be nearly unpredictable as to when the pedestrian has right-of-way without a light. The pedestrian phase is extremely, needlessly short, just enough for pedestrians already at the corner when the light changes to make it across on the green walking man, not enough for someone not there, even when the car phases would make it safe for pedestrians to cross. Drivers only look at traffic lights, not for context, so if you are in the crosswalk (marked or otherwise) you will very much risk getting hit (or at least the ire of the driver) if you do not have a green walking man providing moral and legal support. In many cases these are absurd.
Traffic can flow freely now because drivers can credibly threaten murder. AVs won’t be able to make that threat.
— brad plumer (@bradplumer) July 12, 2017
For instance the figure at Thai Tha Hai restaurant.
- Uneven sidewalks. For a variety of reasons, most sidewalks appear original, although wheelchair curb-cuts have been retrofitted in most places. While roads are periodically resurfaced, the sidewalks, which were likely fairly even when first poured, have unevened with the heave and ho due to poor construction, changing soil conditions, trees, recent construction and the like. Except for the few sidewalks that have been shaved, this leads to tripping hazards. While these hazards are easily identified (send out some interns), it won’t be solved unless someone develops a multi-million dollar robot to ride all the Sydney sidewalks and provide a report, with a large construction contract on the other end.
- Shared paths. Many sidewalks are marked as shared paths with bicycles. This isn’t as much of a problem for the pedestrian as it might seem, since so few people bike. That is a problem for other reasons.
Much of the network is circuitous (see ,,), missing links abound. I previously noted the lack of railway crossings, but there are other issues on the street network. I haven’t tested whether this is especially bad here compared to other places, but subjectively it is noticeable. So for instance my trip from home to work more or less as shown in the image could be much straighter than it is, were there a southern/western crossing of the tracks at Redfern station.
- Crowding. While pedestrian crowding is not common on most sections of sidewalk, there are times are places where this is a problem. (In the map, the path to and from Redfern Station gets crowded at peak times). Crowding is a problem for several reasons. Pedestrian speeds are slowed to the speed of the slowest traveler, so overtaking is required. The sidewalks are narrow in place, worse on trash collection days, when the rubbish and recycling bins are out. The crowding is especially a shame given the use of space to store empty cars on streets, space that could be reclaimed for more productive human movement.
Navigability. While soon our Augmented Reality glasses may make navigation an irrelevancy, in the meantime, I often try to figure out where I am. This requires looking at my phone because there are not street signs visible to pedestrians. The signs are aimed for autos, and on one-way streets for cars (which are still two-way streets for pedestrians), the signs all face the direction the autos are moving.
- Fumes and Noise. Cars and especially trucks and buses produce fumes and noise and other externalities that increase the unpleasantness of walking and lower the pedestrian’s expected lifespan. While electrification will eventually do away with both fumes and noise, trucks will be the last surface vehicles to electrify, so this will likely be a feature on the roads for decades. Given the rate of construction in Sydney, many of these are especially large, loud, and polluting construction-related vehicles.
All of that said, there are plenty of nice parts. Some of the best features of walking in Sydney are below:
- There are some pedestrian only streets (e.g. Kensington, shown)
- There is a lot of traffic calming within shopping streets and neighborhoods. (The effect of the traffic calming is to push more traffic to the signalized arterials, where it is controlled, but now more congested than it otherwise would be.)
- Drivers almost always obey the marked crosswalks if a pedestrian is waiting to cross (though what constitutes ‘waiting to cross’ is a bit ambiguous). (They will not yield at unmarked crosswalks unless the pedestrian is in the street, and even then only reluctantly and with ire.)
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