data

Access to Destinations Data

| David Levinson

Many years ago, we completed a project called Access to Destinations. The data from the project has been sitting on my hard drive for many years. I am happy that some of it is now preserved for posterity and open science by the University of Minnesota Data Conservancy. See:

 

Unfortunately, due to small methodological changes, these data are not directly comparable with more recent outputs, and the 1995 – 2005 data are really not directly comparable with the 2010 data either. It nevertheless might be interesting for selected applications.

Tracking job and housing dynamics with smartcard data | Proceedings of the National Academy of Sciences (open access)

| David Levinson

Recently published:

  • Jie Huang, David Levinson, Jiaoe Wang, Jiangping Zhou, and Zi-jia Wang (2018) Tracking job and housing dynamics with smartcard data  (Open Access) PNAS published ahead of print November 19, 2018 [doi] 

 

F5.medium

Significance

This paper uses transit smartcards from travelers in Beijing retained over a 7-y period to track boarding and alighting stations, which are associated with home and work location. This allows us to track who moves and who remains at their homes and workplaces. Therefore, this paper provides a longitudinal study of job and housing dynamics with group conceptualization and characterization. This paper identifies four mobility groups and then infers their socioeconomic profiles. How these groups trade off housing expenditure and travel time budget is examined.

bubble

Abstract

Residential locations, the jobs–housing relationship, and commuting patterns are key elements to understand urban spatial structure and how city dwellers live. Their successive interaction is important for various fields including urban planning, transport, intraurban migration studies, and social science. However, understanding of the long-term trajectories of workplace and home location, and the resulting commuting patterns, is still limited due to lack of year-to-year data tracking individual behavior. With a 7-y transit smartcard dataset, this paper traces individual trajectories of residences and workplaces. Based on in-metro travel times before and after job and/or home moves, we find that 45 min is an inflection point where the behavioral preference changes. Commuters whose travel time exceeds the point prefer to shorten commutes via moves, while others with shorter commutes tend to increase travel time for better jobs and/or residences. Moreover, we capture four mobility groups: home mover, job hopper, job-and-residence switcher, and stayer. This paper studies how these groups trade off travel time and housing expenditure with their job and housing patterns. Stayers with high job and housing stability tend to be home (apartment unit) owners subject to middle- to high-income groups. Home movers work at places similar to stayers, while they may upgrade from tenancy to ownership. Switchers increase commute time as well as housing expenditure via job and home moves, as they pay for better residences and work farther from home. Job hoppers mainly reside in the suburbs, suffer from long commutes, change jobs frequently, and are likely to be low-income migrants.

Model Accuracy Data for Post-Construction Evaluation of Forecast Accuracy in Minnesota

| David Levinson
thumbnail_optionIt’s important for scientific replicability and progress that datasets be made available. Mostly they are sitting on researchers hard drivers not out of any greed or malice, but sloth and indifference. Making data available for others to use is hard. It requires documenting things that were in your head.
Following more than one request for our data, we put ‘Model Accuracy Data for Post-Construction Evaluation of Forecast Accuracy in Minnesota‘ online at the University of Minnesota Data Repository.
Description
This data was used for the project: Post-Construction Evaluation of Forecast Accuracy Parthasarathi, Pavithra; Levinson, David (Minnesota Department of Transportation, 2009)
and the related paper:
Parthasarathi, Pavithra and David Levinson (2010) Post-Construction Evaluation of Traffic Forecast Accuracy. Transport Policy 17 428-443.
The website has the data and the all-important meta-data. If you are interested, please download and cite back.
If you are doing research currently, try to make your data available upon publication so that others can replicate your work. Researchers may be subject to confidentiality or other constraints for certain kinds of data, some of our data is. Yet many data sets are not so constrained.

Developing a Comprehensive US Transit Accessibility Database

| David Levinson

Recent working paper:

Transit Accessibility in Minneapolis
Transit Accessibility in Minneapolis

Owen, A. and Levinson, D. (2014) Developing a Comprehensive US Transit Accessibility Database

  • This paper discusses the development of a national public transit accessibility evaluation framework, focusing on lessons learned, data source evaluation and selection, calculation methodology, and examples of accessibility evaluation results. In both practice and in research, accessibility evaluation remains experimental and methodologically fragmented. This heightens the “first mover” risk for agencies seeking to implement accessibility-based planning practices, as they must select a method which might produce results that can only be interpreted locally. Development of a common baseline accessibility metric could advance the use of accessibility- based planning. The accessibility evaluation framework described here builds on methods developed in earlier project, extended for use on a national scale and at the Census block level. Application on a national scale involves assembling and processing a comprehensive national database of public transit network topology and travel times. This database incorporates the significant computational advancement of calculating accessibility continuously for every minute within a departure time window of interest. Values for contiguous departure time spans can then be averaged or analyzed for variance over time. This significantly increases computational complexity, but provides a very robust representation of the interaction between transit service frequency and accessibility at multiple departure times.

1920-1995 Twin Cities State Highway Network

| David Levinson

We have posted some additional historic data online at the University of Minnesota’s Digital Conservancy, representing the 1920-1995 Twin Cities State Highway Network. (This is the data visualized in the movie below)

(Digitized historic 1958 Land use maps are available here) (discussed here).

Please use this identifier to cite or link to this item: http://hdl.handle.net/11299/162818

 

Title: 1920-1995 Twin Cities State Highway Network
Authors: Chen, Wei
Levinson, David
Keywords: transportation
GIS
shapefile
Issue Date: 16-Feb-2003
Citation: Chen, Wei and David Levinson. “1920-1995 Twin Cities State Highway Network”. Univ. of Minnesota Digital Conservancy. 2003. http://hdl.handle.net/11299/162818. Accessed: <date accessed>.
Abstract: Vector line data with highway centerlines. Features may have attributes indicating year built and/or year divided. Also includes a PDF illustrating the data.
Description: Illustrates the development of the highway network in the Twin Cities metropolitan region
URI: http://hdl.handle.net/11299/162818
Appears in Collections: Data Sets

 

Files in This Item:

File Description Size Format
Roads1920_1995.pdf PDF representation of vector data. 128.69 kB PDF View/Open
Roads1920_1995_data.zip GIS data — Single shapefile. 54.08 kB ZIP View/Open
Roads1920_1995_original_data.zip Originally submitted data files. See Roads1920_1995_data for simplified download. 139.12 kB ZIP View/Open
Roads1920_1995_metadata.xml Metadata for highways_l shapefile in XML format. 5.95 kB XML View/Open
Roads1920_1995_notice.rtf Notice included as required for data derived from MetroGIS datasets. 1.49 kB RTF View/Open

Linklist: March 19, 2012

| David Levinson

Steven Johnson Why The Bay Area Needs The Bay Lights [Transportation as art]

Created with over 25,000 energy efficient, white LED lights, it is 1½ miles wide and 500 feet high… The Bay Lights is a monumental tour de force seven times the scale of the Eiffel Tower’s 100th Anniversary lighting.

Pioneer Press Planning for [Sprawl in the] South Concord Corridor is in the works:

“A key part of the plan is building a frontage road for I-494 that connects the Hardman Avenue and Concord Street interchanges.

“This convenient frontage road access will open the area up to the market forces generated by the traffic on I-494 and will provide an improved environment for fostering retail, including restaurants,” the study reads.”

Via SR, Pretty cool use of US census data. From Hairycow

Atlantic Cities: Saving Detroit’s Public Transit By Privatizing It [A foot in the door to privatization.]

Authenticated electricity: Sony power outlets will charge you for charging:

“Sony is building a new kind of power outlet that raises a not entirely pleasant prospect—in the future, plugging a phone into a public wall socket might require authentication and take a chunk out of your bank account. But the technology will have many important uses, Sony says, from managing payments for recharging electrical vehicles to avoiding blackouts by intelligently regulating the use of power.”

MasterCard is pitching: Leave the Hassle at Home: Commuting can be Easier with ONE Card for ALL Stops:

“The vast majority of commuters we surveyed think so.  In fact, 72% of respondents in U.S., 85% in Singapore and 86% in South Korea told us they wish there was one card for use across all local mass transit systems. They also estimated that with one payment card they could save close to one hour (55 minutes!) per work week. Well, the capability already exists in MasterCard PayPass and for many, it’s already in your wallet.”

[Yes, I agree, though the time savings is probably exaggerated.].

Baruch Feigenbaum @ Reason says: I-85 Managed Lanes are A Success. [They may or may not be, these data do not prove one way or another yet, since total flows dropped and speeds rose. More people faster would be conclusive (from a transportation perspective, environmentalists would disagree). Fewer people faster is ambiguous, and depends on Value of Time. In percentage terms, speeds rose (3.2% in the GP lanes, 4.6% in the managed lane) more than flows dropped (1.7%)].

Driven Apart

| David Levinson

Joe Cortwright just released a very nice takedown of the TTI Urban Mobility Report (an essential, yet incomplete source of transportation data) Driven Apart. It is well worth reading. From the press release:

A new report from CEOs for Cities relased today unveils the real reason Americans spend so much time in traffic and offers a dramatic critique of the 25 year old industry standard created by the Texas Transportation Institute’s Urban Mobility Report (UMR) – often used to justify billions of dollars in expenditures to build new roads and highways. The surprising analysis by Joseph Cortright, senior policy advisor for CEOs for Cities, says the solution to this problem has much more to do with how we build our cities than how we build our roads.
The report, titled Driven Apart: How sprawl is lengthening our commutes and why misleading mobility measures are making things worse and supported by the Rockefeller Foundation takes a new look at what’s really causing traffic congestion in America and says that compact cities are the real answer to reduscing traffic delays. These conclusions are far different than those of the UMR, which has long been used to measure traffic congestion.