SUPPORTING ROUTE CHOICES VIA REAL-TIME VISUAL TRAFFIC INFORMATION AND COUNTERFACTUAL ARRIVAL TIMES BY DAEHAN KWAK A dissertation submitted to the Graduate School—New Brunswick Rutgers, The State University of New Jersey in partial fulfillment of the requirements for the degree of Doctor of Philosophy Graduate Program in Computer Science Written under the direction of Badri Nath and approved by New Brunswick, New Jersey May, 2017 ABSTRACT OF THE DISSERTATION Supporting Route Choices via Real-time Visual Traffic Information and Counterfactual Arrival Times by Daehan Kwak Dissertation Director: Badri Nath Mobility plays an integral role in modern lives, yet with the ever-expanding number of cars, traffic congestion poses various negative effects, causing vast economic loss, air pollution, and commuter stress. As live traffic information is becoming ubiquitous, route guidance systems are used to inform drivers of route capacities to avoid traffic congestion. Navigation systems compare several different routes and provide the user with options to choose from, from a list of best possible route recommendations. Drivers’ route choice decisions are typically based on the route that minimizes their travel cost (e.g. travel time). However, there are three main limitations for route guidance and information systems. First, as travel time reliability plays an influential role in the driver’s route choice decision-making, the difference in the travel time estimations and/or recommended routes may vary across navigation systems, which can contribute to the uncertainty in the route choice. Second, as the estimated travel time is the dominant deciding factor in route choice, the impact of uncertain, inaccurate, and variable travel time estimations can render it useless, negatively influencing the drivers’ compliance to ii the information system’s recommended route. Third, as drivers cannot assess and compare their actual route choice to the non-chosen foregone alternatives, they face frequent dilemmas over their route-choice decisions, especially when route alternatives recommended by navigation systems are not consistent with their own previous driving experiences. In this dissertation, our focus is to explore these three limitations. First, we present a com- parative analysis on the route recommendations given from four popular online map providers: Google Maps, HERE, MapQuest and Bing Maps. We analyze traffic data collected from all four of the different map providers for 71 days for two cities, each with two origin-destination pairs. Statistical analysis show that the estimated travel times on identical routes are signifi- cantly different among the map providers. This in itself has the potential to create uncertainty in route choices and travel time variability, in addition to a decrease in the credibility and com- pliance with the map provider’s route choice. Second, to complement the deciding factors (e.g., Estimated Time of Arrival (ETA)) in route decisions, we propose a system called So- cial Vehicle Navigation. This system incorporates a secondary level of detail into the vehicle navigation system by providing other semantically rich information that drivers can share with one another. This user-shared visual traffic information assists in the decision-making process and also improves the efficacy in route determinations. Third, we introduce a rationale for counterfactual thinking in route choice, where drivers receive feedback information about the actual travel times on forgone alternatives (i.e. non-chosen routes), so that at the end of the day, drivers have the ability to exercise reinforced learning and self-assessments of their route choices. We propose DoppelDriver, a system that offers a direct, actual travel time compari- son among chosen and non-chosen routes, which determines the actual travel times from probe participatory vehicles on the non-chosen routes. iii The main conclusion of this dissertation is that existing navigation systems have limita- tions and can potentially introduce uncertainty in route choice. To support and improve the driving experience, we address the use of visual traffic information for pre-trip route choice and the use of counterfactual travel times as post-choice feedback information on the forgone alternatives. iv Acknowledgements My deep gratitude first goes to Professor Liviu Iftode, who is no longer with us, but resting in heaven. He has been a great mentor, guiding me through my graduate education, always pushing me forward and motivating me on my research and studies. I have been very fortunate to have an advisor, who has given me freedom to explore first on my own while at the same time, teaching me to strive for constant improvements. His continuous support for the last seven years at Rutgers has been tremendous and I will miss him dearly. I know he will be proud of me. I also want to thank Professor Badri Nath, for taking me under his wings and continuing to support me by being available for discussions and providing helpful feedback for me. Our discussions have turned out to be very constructive, and have helped me sort out the details of my projects. His insights and advices have been invaluable. Professor Nath has provided a wealth of benefits to me as I struggled to complete this work. My gratitude extends to Professor Thu Nguyen and Professor Vinod Ganapathy as well. Professor Thu has always been available for great conversations and guidance for my track for Ph.D. and also job search advices. I have had the pleasure to work with Professor Vinod Ganapathy and he has constantly helped, supported, and shown me encouragements along the way. I would also like to thank Dr. Stephen Smaldone for his support and help as my external committee member. During my time at Rutgers, I have had the pleasure of working with many excellent people. v My appreciation also goes out to my colleagues, Ruilin Liu, Nader Boushehrinejadmoradi, Daeyoung Kim, and Hai Nguyen, whom I have had the pleasure to learn various things from. I especially would like to thank Ruilin Liu and Daeyoung Kim, who have helped me days and nights on my experiments and research and showing great teamwork. Throughout my long journey all of these people have contributed to make my Ph.D. life special. I am grateful to the staff of the department, especially, Carol DiFrancesco, for assisting me in many different ways. I also send my thanks to Gregory Hill, my supervisor, my mentor, and my friend. Getting me through my military services, helping me set up at Rutgers, reviewing my work... You have helped and supported me in endless ways. I greatly appreciate all of what you have done for me. Lastly, I would like to thank my parents for their unconditional love, patience, and support. They add onto my purpose and inspiration. Last but not the least, I am thankful to Amber Kim, for her patience and love while I was working on my Ph.D. I dedicate and owe my dissertation to them. Thank you all!!! vi Dedication To whom I owe everything, my mother and father. To Amber Kim, for your love, trust, and support. vii Table of Contents Abstract ........................................... ii Acknowledgements .................................... v Dedication ......................................... vii List of Tables ........................................ xii List of Figures ....................................... xiii 1. Introduction ...................................... 1 1.1. Travel Information ................................ 2 1.1.1. State-of-the-art on Travel Information .................. 2 1.2. Route Choice ................................... 4 1.2.1. Limitations in Route Choice ....................... 5 1.3. Thesis ....................................... 7 1.4. Summary of Dissertation Contributions ..................... 8 1.5. Contributors to the Dissertation .......................... 10 1.6. Organization of the Dissertation ......................... 11 2. Comparative Analysis on Online Maps ....................... 12 2.1. Introduction .................................... 12 2.2. Background and Related Work .......................... 14 viii 2.3. Experiment Setup ................................. 16 2.4. Data Description ................................. 18 2.5. Descriptive Study ................................. 22 2.5.1. Recommended Route Options ...................... 22 2.5.2. Routes Viewed by Date .......................... 25 2.5.3. Route Changes .............................. 26 2.6. Comparative Study ................................ 26 2.6.1. Case of Best Routes ........................... 26 2.6.2. Case of Identical Routes ......................... 30 2.7. Summary ..................................... 33 3. Real-Time Visual Traffic Information for Pre-trip Route Choice ......... 35 3.1. Introduction .................................... 36 3.2. Related Work ................................... 38 3.2.1. Collaborative Sharing .......................... 38 3.2.2. Route Planning via Traffic Cameras ................... 39 3.3. Social Vehicle Navigation ............................. 40 3.3.1. Example Scenario ............................ 40 3.3.2. Layered Architecture Model ....................... 42 3.4. System Design .................................. 44 3.4.1. Design Consideration ........................... 44 3.4.2. Vehicular Cloud Client .......................... 46 3.4.3. Internet Cloud Design .......................... 48 3.5. Prototype ..................................... 54 ix 3.5.1. Implementation .............................. 54 3.5.2. System