Making Headways: Analysis of Smart Cards and Bus Dwell Times in Los Angeles, California

Document Type

Journal Article

Publication Date


Subject Area

place - north america, place - urban, mode - bus, technology - ticketing systems, technology - passenger information, operations - performance


smart card fare payments, transit bus, dwell time


This report analyzes the impact of smart card fare payments on transit bus dwell time. Shorter dwell times improve travel speeds and reduce headways, which encourage patronage. First, determinants of dwell time are discussed through a review of existing literature. Data from automatic passenger counters and automatic fare collection systems on Los Angeles, California, Metropolitan Transportation Authority buses are then used to estimate a regression model of dwell time by fare payment type, controlling for other factors, including number of passengers boarding and alighting, wheelchairs, bicycles, bus type and configuration, and service (local, express, etc.). An ordinary least squares regression model estimated with those variables explains 45% of the variance in dwell time. Statistically significant coefficients show that smart card payments contributed roughly 2 s per person to dwell time, while cash or other media contributed about 4 s. Using a smart card to purchase a pass or stored value at the fare box contributed about 8 s. While smart cards contributed less to dwell time than did other forms of fare payment, they were not the largest determinants of dwell times overall. An articulated bus, for example, reduced dwell time compared with conventional buses by 3 s on average and as much as 13 s in crowded conditions; similarly, wheelchair boarding and alighting added as much as 35 s. These findings suggest that smart cards can help reduce delays at stops, but their effects were relatively modest compared with those of other factors known to influence dwell time.


Permission to publish the abstract has been given by Transportation Research Board, Washington, copyright remains with them.