TRANSPORTATION RESEARCH BOARD 2024 EXECUTIVE COMMITTEE*

OFFICERS

CHAIR: Carol A. Lewis, Professor, Transportation Studies, Texas Southern University, Houston

VICE CHAIR: Leslie S. Richards, General Manager, Southeastern Pennsylvania Transportation Authority (SEPTA), Philadelphia

EXECUTIVE DIRECTOR: Victoria Sheehan, Transportation Research Board, Washington, DC

MEMBERS

Michael F. Ableson, CEO, Arrival Automotive–North America, Detroit, MI

James F. Albaugh, President and CEO, The Boeing Company (retired), Scottsdale, AZ

Carlos M. Braceras, Executive Director, Utah Department of Transportation, Salt Lake City

Douglas C. Ceva, Vice President, Customer Lead Solutions, Prologis, Inc., Jupiter, FL

Nancy Daubenberger, Commissioner of Transportation, Minnesota Department of Transportation, St. Paul

Marie Therese Dominguez, Commissioner, New York State Department of Transportation, Albany

Garrett Eucalitto, Commissioner, Connecticut Department of Transportation, Newington

Chris T. Hendrickson, Hamerschlag University Professor of Engineering Emeritus, Carnegie Mellon University, Pittsburgh, PA

Randell Iwasaki, President and CEO, Iwasaki Consulting Services, Walnut Creek, CA

Ashby Johnson, Executive Director, Capital Area Metropolitan Planning Organization (CAMPO), Austin, TX

Joel M. Jundt, Secretary of Transportation, South Dakota Department of Transportation, Pierre

Hani S. Mahmassani, W.A. Patterson Distinguished Chair in Transportation; Director, Transportation Center, Northwestern University, Evanston, IL

Scott C. Marler, Director, Iowa Department of Transportation, Ames

Ricardo Martinez, Adjunct Professor of Emergency Medicine, Emory University School of Medicine, Decatur, GA

Michael R. McClellan, Vice President, Strategic Planning, Norfolk Southern Corporation, Atlanta, GA

Russell McMurry, Commissioner, Georgia Department of Transportation, Atlanta

Craig E. Philip, Research Professor and Director, VECTOR, Department of Civil and Environmental Engineering, Vanderbilt University, Nashville, TN

Steward T.A. Pickett, Distinguished Senior Scientist, Cary Institute of Ecosystem Studies, Millbrook, NY

Susan A. Shaheen, Professor and Co-director, Transportation Sustainability Research Center, University of California, Berkeley

Marc Williams, Executive Director, Texas Department of Transportation, Austin

EX OFFICIO MEMBERS

Michael R. Berube, Deputy Assistant Secretary for Sustainable Transportation, U.S. Department of Energy, Washington, DC

Shailen Bhatt, Administrator, Federal Highway Administration, U.S. Department of Transportation, Washington, DC

Amit Bose, Administrator, Federal Railroad Administration, Washington, DC

Tristan Brown, Deputy Administrator, Pipeline and Hazardous Materials Safety Administration, U.S. Department of Transportation, Washington, DC

Steven Cliff, Executive Officer, California Air Resources Board, Sacramento

Rand Ghayad, Senior Vice President, Association of American Railroads, Washington, DC

LeRoy Gishi, Chief, Division of Transportation, Bureau of Indian Affairs, U.S. Department of the Interior, Germantown, MD

William H. Graham, Jr. (Major General, U.S. Army), Deputy Commanding General for Civil and Emergency Operations, U.S. Army Corps of Engineers, Washington, DC

Robert C. Hampshire, Deputy Assistant Secretary for Research and Technology, U.S. Department of Transportation, Washington, DC

Zahra “Niloo” Parvinashtiani, Engineer, Mobility Consultant Solutions, Iteris Inc., Fairfax, VA, and Chair, TRB Young Members Coordinating Council

Sophie Shulman, Deputy Administrator, National Highway Traffic Safety Administration, Washington, DC

Karl Simon, Director, Transportation and Climate Division, U.S. Environmental Protection Agency, Washington, DC

Paul P. Skoutelas, President and CEO, American Public Transportation Association, Washington, DC

Polly Trottenberg, Deputy Secretary of Transportation, U.S. Department of Transportation, Washington, DC

Jim Tymon, Executive Director, American Association of State Highway and Transportation Officials, Washington, DC

Veronica Vanterpool, Acting Administrator, Federal Transit Administration, Washington, DC

Michael Whitaker, Administrator, Federal Aviation Administration, U.S. Department of Transportation, Washington, DC

Vinn White, Deputy Administrator, Federal Motor Carrier Safety Administration, Washington, DC

___________________

^* Membership as of August 2024.

NATIONAL COOPERATIVE HIGHWAY RESEARCH PROGRAM

Implementing Machine Learning
at State Departments of Transportation

A GUIDE

Haley Townsend
Matthew Samach
NOBLIS
Washington, DC

Mecit Cetin
Sherif Ishak
OLD DOMINION UNIVERSITY
Norfolk, VA

Kelly Bare
NOBLIS
Washington, DC

Kaan Ozbay
COGNIUM LLC
Princeton, NJ

Subscriber Categories
Administration and Management • Data and Information Technology • Highways

Research sponsored by the American Association of State Highway and Transportation Officials
in cooperation with the Federal Highway Administration

NATIONAL COOPERATIVE HIGHWAY RESEARCH PROGRAM

Systematic, well-designed, and implementable research is the most effective way to solve many problems facing state departments of transportation (DOTs) administrators and engineers. Often, highway problems are of local or regional interest and can best be studied by state DOTs individually or in cooperation with their state universities and others. However, the accelerating growth of highway transportation results in increasingly complex problems of wide interest to highway authorities. These problems are best studied through a coordinated program of cooperative research.

Recognizing this need, the leadership of the American Association of State Highway and Transportation Officials (AASHTO) in 1962 initiated an objective national highway research program using modern scientific techniques—the National Cooperative Highway Research Program (NCHRP). NCHRP is supported on a continuing basis by funds from participating member states of AASHTO and receives the full cooperation and support of the Federal Highway Administration (FHWA), United States Department of Transportation, under Agreement No. 693JJ31950003.

The Transportation Research Board (TRB) of the National Academies of Sciences, Engineering, and Medicine was requested by AASHTO to administer the research program because of TRB’s recognized objectivity and understanding of modern research practices. TRB is uniquely suited for this purpose for many reasons: TRB maintains an extensive committee structure from which authorities on any highway transportation subject may be drawn; TRB possesses avenues of communications and cooperation with federal, state, and local governmental agencies, universities, and industry; TRB’s relationship to the National Academies is an insurance of objectivity; and TRB maintains a full-time staff of specialists in highway transportation matters to bring the findings of research directly to those in a position to use them.

The program is developed on the basis of research needs identified by chief administrators and other staff of the highway and transportation departments, by committees of AASHTO, and by the FHWA. Topics of the highest merit are selected by the AASHTO Special Committee on Research and Innovation (R&I), and each year R&I’s recommendations are proposed to the AASHTO Board of Directors and the National Academies. Research projects to address these topics are defined by NCHRP, and qualified research agencies are selected from submitted proposals. Administration and surveillance of research contracts are the responsibilities of the National Academies and TRB.

The needs for highway research are many, and NCHRP can make significant contributions to solving highway transportation problems of mutual concern to many responsible groups. The program, however, is intended to complement, rather than to substitute for or duplicate, other highway research programs.

NCHRP RESEARCH REPORT 1122

Project 23-16
ISSN 2572-3766 (Print)
ISSN 2572-3774 (Online)
ISBN 978-0-309-70996-5
Library of Congress Control Number 2024943178

© 2024 by the National Academy of Sciences. National Academies of Sciences, Engineering, and Medicine and the graphical logo are trademarks of the National Academy of Sciences. All rights reserved.

COPYRIGHT INFORMATION

Authors herein are responsible for the authenticity of their materials and for obtaining written permissions from publishers or persons who own the copyright to any previously published or copyrighted material used herein.

Cooperative Research Programs (CRP) grants permission to reproduce material in this publication for classroom and not-for-profit purposes. Permission is given with the understanding that none of the material will be used to imply TRB, AASHTO, APTA, FAA, FHWA, FTA, GHSA, or NHTSA endorsement of a particular product, method, or practice. It is expected that those reproducing the material in this document for educational and not-for-profit uses will give appropriate acknowledgment of the source of any reprinted or reproduced material. For other uses of the material, request permission from CRP.

NOTICE

The research report was reviewed by the technical panel and accepted for publication according to procedures established and overseen by the Transportation Research Board and approved by the National Academies of Sciences, Engineering, and Medicine.

The opinions and conclusions expressed or implied in this report are those of the researchers who performed the research and are not necessarily those of the Transportation Research Board; the National Academies of Sciences, Engineering, and Medicine; the FHWA; or the program sponsors.

The Transportation Research Board does not develop, issue, or publish standards or specifications. The Transportation Research Board manages applied research projects which provide the scientific foundation that may be used by Transportation Research Board sponsors, industry associations, or other organizations as the basis for revised practices, procedures, or specifications.

The Transportation Research Board; the National Academies of Sciences, Engineering, and Medicine; and the sponsors of the National Cooperative Highway Research Program do not endorse products or manufacturers. Trade or manufacturers’ names or logos appear herein solely because they are considered essential to the object of the report.

Published research reports of the

NATIONAL COOPERATIVE HIGHWAY RESEARCH PROGRAM

are available from

National Academies Press
500 Fifth Street, NW, Keck 360
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(800) 624-6242

and can be ordered through the Internet by going to

https://nap.nationalacademies.org

Printed in the United States of America

The National Academy of Sciences was established in 1863 by an Act of Congress, signed by President Lincoln, as a private, nongovernmental institution to advise the nation on issues related to science and technology. Members are elected by their peers for outstanding contributions to research. Dr. Marcia McNutt is president.

The National Academy of Engineering was established in 1964 under the charter of the National Academy of Sciences to bring the practices of engineering to advising the nation. Members are elected by their peers for extraordinary contributions to engineering. Dr. John L. Anderson is president.

The National Academy of Medicine (formerly the Institute of Medicine) was established in 1970 under the charter of the National Academy of Sciences to advise the nation on medical and health issues. Members are elected by their peers for distinguished contributions to medicine and health. Dr. Victor J. Dzau is president.

The three Academies work together as the National Academies of Sciences, Engineering, and Medicine to provide independent, objective analysis and advice to the nation and conduct other activities to solve complex problems and inform public policy decisions. The National Academies also encourage education and research, recognize outstanding contributions to knowledge, and increase public understanding in matters of science, engineering, and medicine.

Learn more about the National Academies of Sciences, Engineering, and Medicine at www.nationalacademies.org.

The Transportation Research Board is one of seven major program divisions of the National Academies of Sciences, Engineering, and Medicine. The mission of the Transportation Research Board is to mobilize expertise, experience, and knowledge to anticipate and solve complex transportation-related challenges. The Board’s varied activities annually engage about 8,500 engineers, scientists, and other transportation researchers and practitioners from the public and private sectors and academia, all of whom contribute their expertise in the public interest. The program is supported by state departments of transportation, federal agencies including the component administrations of the U.S. Department of Transportation, and other organizations and individuals interested in the development of transportation.

Learn more about the Transportation Research Board at www.TRB.org.

COOPERATIVE RESEARCH PROGRAMS

CRP STAFF FOR NCHRP RESEARCH REPORT 1122

Monique R. Evans, Director, Cooperative Research Programs

Waseem Dekelbab, Deputy Director, Cooperative Research Programs, and Manager, National Cooperative Highway Research Program

Sid Mohan, NCHRP Associate Program Manager for Implementation and Technology Transfer

Mireya Kuskie, Senior Program Assistant

Natalie Barnes, Director of Publications

Heather DiAngelis, Associate Director of Publications

NCHRP PROJECT 23-16 PANEL
Field of Administration—Area of Agency Administration

Frances D. Harrison, Spy Pond Partners, LLC, Arlington, MA (Chair)

Majed N. Al-Ghandour, North Carolina Department of Transportation, Raleigh, NC

Daniela Bremmer, Washington State Department of Transportation, Lacey, WA

Ross Cutts, Geosetta, Columbia, MD

Kira Marina Glover-Cutter , Oregon Department of Transportation, Salem, OR

Shashi S. Nambisan, University of Nevada, Las Vegas, Las Vegas, NV

Daniel Tran, University of Kansas, Lawrence, KS

Walter Yu, California Department of Transportation, Sacramento, CA

Mo Zhao, Virginia Transportation Research Council, Charlottesville, VA

Faisal Saleem, FHWA Liaison

Penelope Z. Weinberger, AASHTO Liaison

AUTHOR ACKNOWLEDGMENTS

The authors would like to acknowledge individuals who contributed to this research and its final products. From Noblis, Meenakshy Vasudevan, and Karl Wunderlich served as advisors and provided critical input on the guide and the project overall. From Old Dominion University, Behrouz Salahshour helped with the literature review and compiling the terms for the glossary. The authors also thank the survey respondents and case study interviewees for providing critical inputs to this guide and to the final research report. Their insights and lessons learned will help future machine learning deployers at transportation agencies.

FOREWORD

By Sid Mohan
Staff Officer
Transportation Research Board

NCHRP Research Report 1122: Implementing Machine Learning at State Departments of Transportation: A Guide presents a 10-step roadmap to building agency machine learning (ML) capabilities to (1) educate state departments of transportation (DOTs) on ML applications in transportation; (2) help assess costs, benefits, risks, and limitations of different ML approaches; and (3) assist in building a data-driven organization that can effectively utilize ML. To develop this guide, the research team conducted a review on the state of the art and state of the practice of ML, developed case studies for a variety of data environments, and compiled code examples for major use cases of ML. This publication will be of interest to state DOTs and other stakeholders by providing a foundational understanding of ML and its applications and helping to leverage ML for a safer, more efficient, and sustainable transportation future.

With rapid advances in computing, data science, and big data, there has been a corresponding massive expansion of datasets that are acquired, recorded, and stored and thus available for individuals and organizations to turn into actionable information. Traditional statistical methods, data mining, simulation techniques (e.g., system dynamics and agent-based modeling), and machine learning (ML) are all being used to process these datasets and produce information for decision-making. Categories of ML include supervised learning, unsupervised learning, reinforcement learning, natural language processing, computer vision, and deep learning. Transportation agencies that wish to leverage ML tools and techniques to extract information for decision-making and system operation need to understand and implement these tools as part of their business processes.

In NCHRP Project 23-16, “Implementing and Leveraging Machine Learning at State Departments of Transportation,” Old Dominion University was asked to develop research products on how to select and implement appropriate ML techniques, by identifying promising applications; by assessing costs, benefits, risks, and limitations; and by developing a roadmap for an agency ML program that includes implementation best practices. The research team (1) performed an in-depth literature review and survey of state DOTs on the state of the art and the state of the practice on ML; (2) conducted case studies with five state DOTs to document existing and potential near-term ML applications; (3) compiled illustrative available codes and tools for major use cases of ML; (4) developed a guide on how to select and implement appropriate ML techniques; and (5) developed a briefing document, along with a set of presentation slides highlighting the opportunities offered by ML.

In addition to the research report, the following deliverables are available on the National Academies Press website (nap.nationalacademies.org) by searching for NCHRP Research Report 1122: Implementing Machine Learning at State Departments of Transportation:

• NCHRP Web-Only Document 404: Implementing and Leveraging Machine Learning at State Departments of Transportation, which documents the overall research effort;
• A briefing document on ML at state DOTs;
• A 2-page elevator pitch on ML; and
• ML in Transportation Powerpoint slides.

CONTENTS

Chapter 1 Introduction

Target Audience of the Guide

Purpose of the Guide

Guide Key Takeaways

Chapter 2 Roadmap to Building Agency Machine Learning Capabilities

Overview of the Roadmap

Step 0: Develop Understanding

Step 1: Identify Use Cases

Decision Gate #1

Step 2: Assess Gaps

Step 3: Build Business Case

Decision Gate #2

Step 4: Plan Pilot

Step 5: Execute Pilot

Step 6: Communicate Results

Step 7: Scale Deployment

Step 8: Operations & Maintenance

Step 9: Expand ML Capabilities

References

Glossary of Key Terms

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