Travel Demand Forecasting

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NATIONAL
COOPERATIVE
HIGHWAY
RESEARCH
NCHRP PROGRAM
REPORT 716
Travel Demand Forecasting:
Parameters and Techniques
TRANSPORTATION RESEARCH BOARD 2012 EXECUTIVE COMMITTEE*
OFFICERS
Chair: Sandra Rosenbloom, Professor of Planning, University of Arizona, Tucson
ViCe Chair: Deborah H. Butler, Executive Vice President, Planning, and CIO, Norfolk Southern Corporation, Norfolk, VA
exeCutiVe DireCtor: Robert E. Skinner, Jr., Transportation Research Board
MEMBERS
J. Barry Barker, Executive Director, Transit Authority of River City, Louisville, KY
William A.V. Clark, Professor of Geography and Professor of Statistics, Department of Geography, University of California, Los Angeles
Eugene A. Conti, Jr., Secretary of Transportation, North Carolina DOT, Raleigh
James M. Crites, Executive Vice President of Operations, Dallas-Fort Worth International Airport, TX
Paula J. C. Hammond, Secretary, Washington State DOT, Olympia
Michael W. Hancock, Secretary, Kentucky Transportation Cabinet, Frankfort
Chris T. Hendrickson, Duquesne Light Professor of Engineering, Carnegie-Mellon University, Pittsburgh, PA
Adib K. Kanafani, Professor of the Graduate School, University of California, Berkeley
Gary P. LaGrange, President and CEO, Port of New Orleans, LA
Michael P. Lewis, Director, Rhode Island DOT, Providence
Susan Martinovich, Director, Nevada DOT, Carson City
Joan McDonald, Commissioner, New York State DOT, Albany
Michael R. Morris, Director of Transportation, North Central Texas Council of Governments, Arlington
Tracy L. Rosser, Vice President, Regional General Manager, Wal-Mart Stores, Inc., Mandeville, LA
Henry G. (Gerry) Schwartz, Jr., Chairman (retired), Jacobs/Sverdrup Civil, Inc., St. Louis, MO
Beverly A. Scott, General Manager and CEO, Metropolitan Atlanta Rapid Transit Authority, Atlanta, GA
David Seltzer, Principal, Mercator Advisors LLC, Philadelphia, PA
Kumares C. Sinha, Olson Distinguished Professor of Civil Engineering, Purdue University, West Lafayette, IN
Thomas K. Sorel, Commissioner, Minnesota DOT, St. Paul
Daniel Sperling, Professor of Civil Engineering and Environmental Science and Policy; Director, Institute of Transportation Studies; and Acting
Director, Energy Efficiency Center, University of California, Davis
Kirk T. Steudle, Director, Michigan DOT, Lansing
Douglas W. Stotlar, President and CEO, Con-Way, Inc., Ann Arbor, MI
C. Michael Walton, Ernest H. Cockrell Centennial Chair in Engineering, University of Texas, Austin
EX OFFICIO MEMBERS
Rebecca M. Brewster, President and COO, American Transportation Research Institute, Smyrna, GA
Anne S. Ferro, Administrator, Federal Motor Carrier Safety Administration, U.S.DOT
LeRoy Gishi, Chief, Division of Transportation, Bureau of Indian Affairs, U.S. Department of the Interior, Washington, DC
John T. Gray II, Senior Vice President, Policy and Economics, Association of American Railroads, Washington, DC
John C. Horsley, Executive Director, American Association of State Highway and Transportation Officials, Washington, DC
Michael P. Huerta, Acting Administrator, Federal Aviation Administration, U.S.DOT
David T. Matsuda, Administrator, Maritime Administration, U.S.DOT
Michael P. Melaniphy, President and CEO, American Public Transportation Association, Washington, DC
Victor M. Mendez, Administrator, Federal Highway Administration, U.S.DOT
Tara O’Toole, Under Secretary for Science and Technology, U.S. Department of Homeland Security, Washington, DC
Robert J. Papp (Adm., U.S. Coast Guard), Commandant, U.S. Coast Guard, U.S. Department of Homeland Security, Washington, DC
Cynthia L. Quarterman, Administrator, Pipeline and Hazardous Materials Safety Administration, U.S.DOT
Peter M. Rogoff, Administrator, Federal Transit Administration, U.S.DOT
David L. Strickland, Administrator, National Highway Traffic Safety Administration, U.S.DOT
Joseph C. Szabo, Administrator, Federal Railroad Administration, U.S.DOT
Polly Trottenberg, Assistant Secretary for Transportation Policy, U.S.DOT
Robert L. Van Antwerp (Lt. Gen., U.S. Army), Chief of Engineers and Commanding General, U.S. Army Corps of Engineers, Washington, DC
Barry R. Wallerstein, Executive Officer, South Coast Air Quality Management District, Diamond Bar, CA
Gregory D. Winfree, Acting Administrator, Research and Innovative Technology Administration, U.S.DOT
*Membership as of March 2012.
N A T I O N A L C O O P E R A T I V E H I G H W A Y R E S E A R C H P R O G R A M
NCHRP REPORT 716
Travel Demand Forecasting:
Parameters and Techniques
Cambridge Systematics, Inc.
Cambridge, MA
Vanasse Hangen Brustlin, Inc.
Silver Spring, MD
Gallop Corporation
Rockville, MD
Chandra R. Bhat
Austin, TX
Shapiro Transportation Consulting, LLC
Silver Spring, MD
Martin/Alexiou/Bryson, PLLC
Raleigh, NC
Subscriber Categories
Highways • Operations and Traffc Management • Planning and Forecasting • Safety and Human Factors
Research sponsored by the American Association of State Highway and Transportation Offcials
in cooperation with the Federal Highway Administration
T R A NSPORTAT ION RESEARCH BOARD
WASHINGTON, D.C.
2012
www.TRB.org
NATIONAL COOPERATIVE HIGHWAY NCHRP REPORT 716
RESEARCH PROGRAM
Systematic, well-designed research provides the most effective Project 08-61
approach to the solution of many problems facing highway ISSN 0077-5614
administrators and engineers. Often, highway problems are of local ISBN 978-0-309-21400-1
Library of Congress Control Number 2012935156
interest and can best be studied by highway departments individually
or in cooperation with their state universities and others. However, the © 2012 National Academy of Sciences. All rights reserved.
accelerating growth of highway transportation develops increasingly
complex problems of wide interest to highway authorities. These
problems are best studied through a coordinated program of
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C O O P E R A T I V E R E S E A R C H P R O G R A M S
CRP STA F OF R CN HRP REPORT 617
Christopher W. Jenks, Director, Cooperative Research Programs
Crawford F. Jencks, Deputy Director, Cooperative Research Programs
Nanda Srinivasan, Senior Program Offcer
Charlotte Thomas, Senior Program Assistant
Eileen P. Delaney, Director of Publications
Natalie Barnes, Senior Editor
CN HRP PROEJ CT 16-80 PAEN L
Field of Transportation Planning—Area of Forecasting
Thomas J. Kane, Thomas J. Kane Consulting, Urbandale, IA (Chair)
Michael S. Bruff, North Carolina DOT, Raleigh, NC
Ed J. Christopher, Berwyn, IL
Nathan S. Erlbaum, New York State DOT, Albany, NY
Jerry D. Everett, University of Tennessee, Knoxville, TN
Bruce Griesenbeck, Sacramento Area Council of Governments, Sacramento, CA
Herbert S. Levinson, Wallingford, CT
Richard H. Pratt, Richard H. Pratt, Consultant, Inc., Garrett Park, MD
Bijan Sartipi, California DOT, Oakland, CA
Shuming Yan, Washington State DOT, Seattle, WA
Ken Cervenka, FTA Liaison
Kimberly Fisher, TRB Liaison
ATU HOR ACONK ELW GD METN S
The research project reported herein was performed under NCHRP Project 8-61 by Cambridge
Systematics, Inc. in association with Dr. Chandra R. Bhat, Vanasse Hangen Brustlin, Inc., Martin/
Alexiou/Bryson, PLLC, Gallop Corporation, and Shapiro Transportation Consulting, LLC. Cambridge
Systematics served as prime contractor.
Thomas Rossi of Cambridge Systematics served as project director and principal investigator. Major
roles in this project were also performed by David Kurth, John (Jay) Evans, Daniel Beagan, Bruce Spear,
Robert Schiffer, and Ramesh Thammiraju of Cambridge Systematics; Dr. Chandra Bhat; Richard Roisman,
formerly of Vanasse Hangen Brustlin; Philip Shapiro of Shapiro Transportation Consulting (formerly of
Vanasse Hangen Brustlin); C.Y. Jeng of Gallop Corporation; William Martin of Martin/Alexiou/Bryson;
and Amlan Banerjee and Yasasvi Popuri, formerly of Cambridge Systematics.
A peer review panel provided valuable comments on the draft report. The research team wishes to thank
the peer review panel members: Charles Baber of the Baltimore Metropolitan Council, Bart Benthul of
the Bryan-College Station Metropolitan Planning Organization (MPO), Mike Conger of the Knoxville
Regional Transportation Planning Organization, Ken Kaltenbach of the Corradino Group, Phil Matson
of the Indian River MPO, Phil Mescher of the Iowa Department of Transportation, Jeremy Raw of the
Federal Highway Administration, and David Schmitt of AECOM.
The research team wishes to thank the following organizations and individuals for their assistance:
Nancy McGuckin, Ron Milone of the Metropolitan Washington Council of Governments, and Jeffrey
Agee-Aguayo of the Sheboygan MPO.
F O R E W O R D
By Nanda Srinivasan
Staff Offcer
Transportation Research Board
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C O N T E N T S
1 Chapter 1 Introduction
1 1.1 Background
2 1.2 Travel Demand Forecasting: Trends and Issues
3 1.3 Overview of the Four-Step Travel Modeling Process
5 1.4 Summary of Techniques and Parameters
5 1.5 Model Validation and Reasonableness Checking
5 1.6 Advanced Travel Analysis Procedures
5 1.7 Case Study Applications
5 1.8 Glossary of Terms Used in This Report
7 Chapter 2 Planning Applications Context
7 2.1 Types of Planning Analyses
10 2.2 Urban Area Characteristics Affecting Planning and Modeling
41 Chapter 3 Data Needed for Modeling
14 3.1 Introduction
14 3.2 Socioeconomic Data and Transportation Analysis Zones
18 3.3 Network Data
24 3.4 Validation Data
72 Chapter 4 Model Components
27 4.1 Introduction
31 4.2 The Logit Model
33 4.3 Vehicle Availability
37 4.4 Trip Generation
43 4.5 Trip Distribution
48 4.6 External Travel
53 4.7 Mode Choice
58 4.8 Automobile Occupancy
62 4.9 Time of Day
65 4.10 Freight/Truck Modeling
72 4.11 Highway Assignment
77 4.12 Transit Assignment
08 Chapter 5 Model Validation and Reasonableness Checking
80 5.1 Introduction
80 5.2 Model Validation Overview
81 5.3 M odel Validation and Reasonableness Checking Procedures
for Existing Models
86 5.4 M odel Validation and Reasonableness Checking Procedures for Models or
Model Components Developed from Information Contained in Chapter 4
88 5.5 Cautions Regarding Use of This Report for Validation
89 Chapter 6 Emerging Modeling Practices
90 6.1 The Activity-Based Approach
92 6.2 Activity-Based Travel Model Systems in Practice
96 6.3 Integration with Other Model Systems
99 6.4 Summary
100 Chapter 7 Case Studies
100 7.1 Introduction
100 7.2 Model Reasonableness Check
108 7.3 M odel Development Case Study for a Smaller Area without Data
for Model Estimation
114 References
A-1 Appendix A Federal Planning and Modeling Requirements
B-1 Appendix B Review of Literature on Transferability Studies
C-1 Appendix C Transferable Parameters
Note: Many of the photographs, fgures, and tables in this report have been converted from color to grayscale
for printing. The electronic version of the report (posted on the Web at www.trb.org) retains the color versions.
1
C h a p t e r 1
Introduction
1.1 Background planning issues (e.g., environmental, air quality, freight,
multimodal, and other critical concerns).
In 1978, the Transportation Research Board (TRB) published One of the features of this report is the provision of trans-
NCHRP Report 187: Quick-Response Urban Travel Estimation ferable parameters for use when locally specifc data are not
Techniques and Transferable Parameters (Sosslau et al., 1978). available for use in model estimation. The parameters pre-
This report described default parameters, factors, and manual sented in this report are also useful to practitioners who are
techniques for doing planning analysis. The report and its modeling urban areas that have local data but wish to check
default data were used widely by the transportation planning the reasonableness of model parameters estimated from such
profession for almost 20 years. In 1998, drawing on several data. Additionally, key travel measures, such as average travel
newer data sources, including the 1990 Census and Nation- times by trip purpose, are provided for use in checking
wide Personal Transportation Survey, an update to NCHRP model results. Both the transferable parameters and the
Report 187 was published in the form of NCHRP Report 365: travel measures come from two main sources: the 2009
Travel Estimation Techniques for Urban Planning (Martin and National Household Travel Survey (NHTS) and a database
McGuckin, 1998). of model documentation for 69 metropolitan planning
Since NCHRP Report 365 was published, signifcant changes organizations (MPOs) assembled for the development of
have occurred affecting the complexity, scope, and context this report. There are two primary ways in which planners
of transportation planning. Transportation planning tools can make use of this information:
have evolved and proliferated, enabling improved and more
fexible analyses to support decisions. The demands on trans- 1. Using transferable parameters in the development of travel
portation planning have expanded into special populations model components when local data suitable for model
and broader issues (e.g., safety, congestion, pricing, air quality, development are insuffcient or unavailable; and
environment, climate change, and freight). In addition, the 2. Checking the reasonableness of model outputs.
default data and parameters in NCHRP Report 365 need to
be updated to refect the planning requirements of today and This report is written at a time of exciting change in the
the next 10 years. feld of travel demand forecasting. The four-step modeling
The objective of this report is to revise and update NCHRP process that has been the paradigm for decades is no longer
Report 365 to refect current travel characteristics and to pro- the only approach used in urban area modeling. Tour- and
vide guidance on travel demand forecasting procedures and activity-based models have been and are being developed in
their application for solving common transportation problems. several urban areas, including a sizable percentage of the largest
It is written for “modeling practitioners,” who are the public areas in the United States. This change has the potential to
agency and private-sector planners with responsibility for devel- signifcantly improve the accuracy and analytical capability
oping, overseeing the development of, evaluating, validating, of travel demand models.
and implementing travel demand models. This updated report At the same time, the four-step process will continue to be
includes the optional use of default parameters and appropriate used for many years, especially in the smaller- and medium-
references to other more sophisticated techniques. The report sized urban areas for which this report will remain a valuable
is intended to allow practitioners to use travel demand fore- resource. With that in mind, this report provides information
casting methods to address the full range of transportation on parameters and modeling techniques consistent with the