Dynamic Ridesharing

Most cars carry at least four passangers, but the average auto occupancy rate for all trips in the US is only 1.6 persons. Because all the empty seats in cars represent our greatest source of untapped transportation capacity, promoting ridesharing is of considerable interest. Government agencies across the country employ ridesharing programs both to provide transportation at low cost and to reduce traffic congestion and the other costs of solo driving. The rigidity of conventional ridesharing arrangements, which generally require fixed travel times, presents a barrier to many people. But developments in computing and communications, however, now allow drivers and potential passengers to match up with little advance planning and no long-term commitments. Local governments, private companies, and nonprofit organizations alike have been pursuing this “dynamic ridesharing” strategy. Participants in these programs use cell phones or computer messaging to match up “on the fly” or up to several days in advance. Travelers submit a ride offer or request and a ridematching ser vice automatically scans its database to identify other offers and requests for trips with similar origins, destinations, and arrival times. If a satisfactory match exists, the service notifies the driver and rider(s) so they can confirm the trip plans.