Investigating Real-Time Employer-Based Ridesharing Preferences Based on Stated Preference Survey Data THESIS Presented in Partial Fulfillment of the Requirements for the Degree Master of Science in the Graduate School of The Ohio State University By Nathan Michael Shay Graduate Program in Civil Engineering The Ohio State University 2016 Master's Examination Committee: Dr. Mark McCord, Co-Advisor Dr. Rabi Mishalani, Co-Advisor Dr. Gulsah Akar Copyrighted by Nathan Michael Shay 2016 Abstract Expanding travel choices by providing ridesharing can improve mobility and accessibility and reduce congestion and the negative externalities associated with single occupancy automobile use. To realize these benefits, sufficient demand must be generated by matching drivers and passengers with similar origins and destinations and who are willing to travel with potential strangers. Technological developments have facilitated the provision of real-time ridesharing programs, where travelers are matched to share a ride shortly before they travel. Real-time ridesharing offers additional flexibility and the possibility of occasional use that may be desirable in an increasingly complex society with varying schedules. While initial real-time travel options have been perceived as unattractive due to reliability and personal safety concerns, the growing success of real-time ride-sourcing services suggests that perceptions may be shifting. Furthermore, large employer-based ridesharing offers additional promise due to a network of co- workers with similar work locations facilitating good matches, increased familiarity with fellow travelers, and the ability to incentivize participation. A stated preference survey of The Ohio State University community was used to analyze willingness to participate in an idealized real-time employer-based ridesharing program. Individual characteristics and travel behaviors associated with unwillingness to ii participate in an ideal program are analyzed. Also, the characteristics and behaviors associated with interest in a passenger or driver role in such a program are identified. Many findings support results presented elsewhere and a priori expectations, for example an increased willingness of younger travelers to participate in ridesharing, an increased willingness of females to participate as passengers, and an increased willingness of those with experience driving to participate as drivers. In addition three findings provide important insights previously unidentified about traveler preferences toward ridesharing. Firstly, it seems that those who travel in automobiles, whether shared or alone, are more likely than those who do not travel in automobiles to participate in ridesharing. Also, those who walk or use transit seem to be less willing to participate in a ridesharing program than those who do not use these alternative modes. These findings are encouraging in light of the desire to attract single occupancy vehicle users, rather than transit users or walkers, to ridesharing to realize its social benefits. Secondly, the notion that providing ridesharing expands mobility and accessibility seems to be supported by the fact that those who do not have a car available to them tend to be more interested in being rideshare passengers than those who have a car available to them. Lastly, while those living with younger dependent children are more likely to reject ridesharing due to the constraints associated with this mode, among those who are interested in ridesharing, individuals living with children—whether younger dependent ones or otherwise—are more willing to drive in a ridesharing program than those who do not live with children, possibly due to having experience traveling in vehicles with passengers. iii Dedication This document is dedicated to Ronald Francis Shay. iv Acknowledgments Firstly, I would like to express my gratitude to my co-advisors Dr. Mark R. McCord and Dr. Rabi G. Mishalani. They provided the vital input necessary to complete this thesis as well as guiding my work as a graduate research associate in the Campus Transit Lab under the auspices of the Department of Civil, Environmental, and Geodetic Engineering at The Ohio State University. Our spirited discussions were not only the driving force behind a thesis I can be proud of, but also some of the most valuable educational experiences of my academic career. The analysis presented in this study would not be possible without the valuable work of Nicole Sell in designing the stated preference survey and Chris Holloman of the Ohio State University’s Statistical Consulting Services in implementing and administering the survey as well as compiling the resulting data. This research is financially supported by Region 5 University Transportation Center funded by US Department of Transportation (DOT), Office of the Assistant Secretary for Research and Technology (OST-R) (Grant no. DTRT12-UTC05) with additional financial support provided by The Ohio State University. The views, opinions, findings, and conclusions presented in this thesis are the responsibility of the author and co-advisors and do not represent the official policy or position of any of these entities or any others. v I would also like to acknowledge the entities that provided funding for my graduate education. I would like to thank the Graduate School at The Ohio State University for the generous award of a University Fellowship. I would also like to acknowledge the gracious support of Tau Beta Pi, the engineering honor society, for the award of a Tau Beta Pi-Fife Fellowship. Finally, I would like to offer my gratitude to the Ohio Chapter of the American Public Works Association for the award of a graduate scholarship. All of this support allowed me to focus on my studies and make the most of my graduate education. vi Vita 2014 ............................................................ B.S. Civil Engineering, Ohio Northern University 2015 to Present ............................................ Graduate Research Associate, Department of Civil Engineering, The Ohio State University 2016 to present ........................................... Associate Engineer/Planner/Modeler, Mid- Ohio Regional Planning Commission Fields of Study Major Field: Civil Engineering vii Table of Contents Abstract .......................................................................................................................... ii Dedication ..................................................................................................................... iv Acknowledgments ...........................................................................................................v Vita .............................................................................................................................. vii Table of Contents ........................................................................................................ viii List of Tables................................................................................................................. xi List of Figures .............................................................................................................. xii Chapter 1: Introduction ....................................................................................................1 1.1 Motivation..............................................................................................................1 1.2 Scope .....................................................................................................................7 1.3 Organization...........................................................................................................8 Chapter 2: Survey Data .................................................................................................. 10 2.1 Overview ............................................................................................................. 10 2.2 Survey .................................................................................................................. 10 2.3 Sample and Response Rates ................................................................................. 15 viii Chapter 3: Methodology ................................................................................................ 19 3.1 Overview ............................................................................................................. 19 3.2 Logit Model Estimation Methodology .................................................................. 19 3.3 Dependent and Explanatory Variable Processing, Definition, and Motivations ..... 22 3.3.1 Data Processing ............................................................................................. 22 3.3.2 Variable Definitions and Motivations ............................................................. 24 3.4 Modeling Structures ............................................................................................. 34 Chapter 4: Modeling Unwillingness to Participate in Ridesharing .................................. 51 4.1 Overview ............................................................................................................. 51 4.2 Model Specification ............................................................................................. 52 4.3 Model Results ...................................................................................................... 58 4.4 Model Interpretation ............................................................................................