Assessment and Refinement of Real-Time Travel Time
Algorithms for Use in Practice
Research Focus
The Federal Highway Administration (FHWA) has set a high
priority on the use of existing dynamic message signs (DMS)
to provide travel time estimates to the public. The Oregon
Department of Transportation (ODOT) currently has three
DMS in the Portland metropolitan area configured to
display travel time information. In the near future, ODOT
would like to make travel time estimates available on
additional DMS, over the Internet on tripcheck.com and via
511. Travel time estimates are valuable to the traveling
public; however, the estimates must be accurate to be
useful. The FHWA indicates that 90% accuracy is ideal and
suggests a minimum accuracy of 80%. Thus, in order to
display travel time estimates, it is essential to
understand the accuracy of the estimates.
The purpose of this study is to extend prior travel time
research conducted at Portland State University with
additional data collection and analysis to provide
statistical confidence in travel time estimates and to
determine the best travel time estimation approach for
ODOT. Ground truth data in the form of probe vehicle runs
will be collected and travel time estimates will be
evaluated using that data. Several travel time estimation
algorithms will be evaluated and modifications to existing
algorithms will be proposed. In addition, this project
will provide analysis to help understand the reliability
and performance of the algorithms under various conditions
(free-flow, congestion, incidents). A methodology will be
developed for determining if travel time estimates fall
within an acceptable accuracy limits. At the conclusion of
the project, it is desired that a methodology can be
recommended that will provide accurate measures of travel
time for use with DMS, the Internet and 511 applications.
This project is a collaboration between faculty, staff and
students in the
Data and Information Management Laboratory
of the Computer Science
Department and the
Intelligent Transportation Systems Laboratory
of the Civil &
Environmental Engineering Department in the Maseeh College
of Engineering and Computer Science at Portland State
University.
This project is funded by the Oregon Department of
Transportation, ITS unit and the
Oregon Transportation Research and
Education Consortium
Any opinions, findings, and conclusions or recommendations
expressed in this material are those of the author(s) and do
not necessarily reflect the views of the Oregon Department
of Transportation or OTREC.
People
Publications and Products
Publications (Papers and Proceedings)
- Kothuri, S., Tufte, K., Fayed, E., and Bertini, R.L.
.Toward Understanding and Reducing Errors in Real-Time
Estimation of Travel Times.. Transportation Research
Record: Journal of the Transportation Research Board,
Transportation Research Board of the National Academies,
Washington, D.C., 2008. (Submitted)
- Kothuri, S., Tufte, K., Hagedorn, H., Bertini, R.L., and
Deeter, D., .Survey of Best Practices in Real Time Travel
Time Estimation and Prediction,. Compendium of Technical
Papers, Institute of Transportation Engineers, District 6
Annual Meeting, Portland, Oregon, July 15-18, 2007.
Reports
- Tufte, K., and Kothuri, S. Assessment and Refinement
of Real-Time Travel Time Algorithms for use in Practice.
Final Report. Submitted to Oregon Department of
Transportation June 2007.