Please join us for the Change Seminar tomorrow *Tuesday 5/15/2018 *in *EEB 037.* *Who: *Dominic Widdows, Grab *What: *GrabShare: The construction of a realtime ridesharing service in Southeast Asia *When: *Tuesday, May 15 12-1pm *Where: *EEB 037 *GrabShare: The construction of a realtime ridesharing service in Southeast Asia* Ridesharing is a natural option for increasing the efficiency and availability of transportation, and many factors need to align for ridesharing to successfully meet user needs in the marketplace. This talk explains how some of these issues have been addressed in the creation of GrabShare, a realtime ridesharing service available in an increasing number of Southeast Asian cities including Singapore, Manila, Kuala Lumpur, and Jakarta. From an algorithmic point of view, the central topic is the scheduling system, which, given passenger bookings and vehicle locations, assigns passengers to vehicles and creates routes for those vehicles to follow. Other crucial factors include pricing, a navigable and reliable user experience, a system architecture robust to rejections and cancellations, and computationally tractable use of maps and traffic resources. A continuing dedication to understanding each city's individual needs and challenges, and persistent attention to user feedback, is also vital. This paper at https://ieeexplore.ieee.org/document/8056896/ gives an account of these areas, and attempts to give an organic overview of how GrabShare helps to serve customers as part of an integrated suite of transportation services throughout Southeast Asia. *Bio:* Dominic came to Grab after several years working on local search at Microsoft, commerce and logistics at Google, natural language processing and machine learning at Stanford, and a few other places along the way. He started off as a differential geometer at Oxford developing quaternion algebraic geometry, and is still applying geometry to various problem areas. In 2000 he moved to California and worked on natural language processing at Stanford, mainly using graph theory and linear algebra to model word meanings, which led to the application of quantum logic in word vector models. He continues this work as an open-source owner of the SemanticVectors package and steering committee member for the Quantum Interaction conference series. High points of his time at Google included building the first routing and delivery system for the project that became Google Shopping Express, and organizing the star data, matrix transformations, and time travel feature for Google Sky Map. (If you have an Android phone and any interest in backyard astronomy, this is still a very fun and useful app to play with!) Most of his work at Microsoft was in local search and information extraction of business listings from the web. So far at Grab he’s worked on designing and building the first versions of GrabShare and GrabExpress, and is now mainly focussing on NLP and AI challenges with Southeast Asian languages, particularly Indonesian and Malaysian.