University of California Transportation Center

This paper studies the effects of certain incentives designed to promote ridesharing on work trips to reduce congestion and air pollution. Ordered probit discrete choice models of commuters' mode choices (always rideshare, sometimes rideshare, and always drive alone) are estimated using a new study of full-time workers' commuting behavior in the greater Los Angeles area. We find that women and those who have larger households with multiple workers, longer commutes, and larger worksites are more likely to rideshare. Partial equilibrium policy simulations with our model indicate that providing all workers with reserved parking, ridesharing subsidies, guaranteed rides home, and high-occupancy vehicle lanes would reduce drive-alone commuting between 11 and 18 percent.