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There is now a CONTENT FREEZE for Mercury while we switch to a new platform. It began on Friday, March 10 at 6pm and will end on Wednesday, March 15 at noon. No new content can be created during this time, but all material in the system as of the beginning of the freeze will be migrated to the new platform, including users and groups. Functionally the new site is identical to the old one. webteam@gatech.edu
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Title: Integrating Behavior, Economics, and Operations in Urban Mobility: Ridesharing and Multi-Modal Travel
Abstract: In today’s urban mobility marketplaces, both operational policies (e.g., matching, routing) and economic policies (e.g., pricing, incentives) affect perceptions of Quality of Service (QoS) and users’ mobility choices. These, in turn, affect both operational objectives (e.g., utilization, vehicle-miles travelled) and economic objectives (e.g., profit, welfare). We study such complex interactions between behavior, economics, and operations in two settings. First, for a commercial ridesharing service provider, we study the problem of pricing exclusive vs. pooled service to maximize profit, while incorporating QoS guarantees (motivated by recent field experiments that highlight the importance of proactively compensating users when they experience frustrations during service). We introduce a dynamic notion of QoS, called sequential individual rationality, that captures users’ behavior-driven responses to the sequence of utilities that they experience during the successive stages of a shared ride, as new users are added. Subsequent analysis of the provider’s QoS-sensitive profit not only yields the optimal QoS-aware pricing policy, but also reveals key operational insights, such as an elegant characterization of optimal “shareable regions”. Our framework is general and can be, for example, adapted to the peer-to-peer carpooling context, where the problem involves finding QoS-aware, fair cost sharing schemes. (This part of the talk is based on joint work with Theja Tulabandhula and Koyel Mukherjee.) Next, we shift our focus from a commercial to a societal perspective, where we study the problem of designing a centralized market for urban mobility that increases social welfare, while ensuring voluntary participation from multiple stakeholders (such as the commuters, non-profit public transit agencies, and profit-sensitive on-demand service providers). We show that multi-modal travel, as an operational handle, can significantly soften the dependence of such mechanisms on external subsidies (mandated by fundamental impossibility results in mechanism design), by favorably exploiting structural properties of a city’s transportation network. (This part of the talk is based on ongoing work with Chamsi Hssaine, Siddhartha Banerjee, and Samitha Samaranayake.) Our results in both settings emphasize the importance of an integrated approach for tackling the next generation of challenges facing urban mobility.
Bio: Raga Gopalakrishnan is a postdoctoral associate in the School of Civil and Environmental Engineering, jointly with the School of Operations Research and Information Engineering, at Cornell University. His research concerns the design of service systems with strategic entities, especially the interplay between operational policies and economic mechanisms, with a growing focus on applications to urban transportation. His interdisciplinary work emphasizes a practice-aware approach to operations research, and combines tools from multiple subjects such as optimization, probability, queueing theory, decision theory, game theory and mechanism design. Raga obtained his Ph.D. from the Department of Computing and Mathematical Sciences at California Institute of Technology in 2013, following which he was a research associate at the University of Colorado Boulder, and a research scientist and manager at Xerox Research.
