Modeling Land Use, Bus Ridership and Air Quality: A Case Study of Chicago Bus Service

1. Modeling Land Use, Bus Ridership and Air Quality: A Case Study of Chicago Bus Service Jie (Jane) Lin, Ph.D., Assistant Professor, MinyanRuana (PhD student) Department of Civil and Materials Engineering & Institute for Environmental Science and Policy • Fifty-five CTA bus routes covering 9 neighborhood type with distinct characteristics are studied between 2001 and 2003. • An effective public transit system will reduce traffic pollution by attracting more passengers from auto drive. • Public transit accessibility and ridership are affected by land use in the neighboring areas along the transit lines. • Investigating the relations between land use features and bus ridership will help find way to improve the air quality. • A mixed regression model with heterogeneity among routes, via random effects, and autocorrelation over time, via autoregressive error terms was built. • The first-order autoregressive error structure AR(1) and Toeplitz TOEP(h) error structure are tested. • The unit ridership daily bus emission (defined as daily bus emission per ridership by route) was estimated using the Chicago-specific summer and winter input parameters for PM10 and NOX. • The set of possible covariates include features in Transit service, sociodemographics and land use by neighborhood type, and 11 month dummy variables refer to January . • The unit ridership daily bus emission will decrease if stops are added in the route. • Total population in the urban non-Hispanic Black neighborhoods is positively correlated with unit ridership daily bus emission due to low employment rates, poor connectivity to transit, and therefore low transit users in general . • High road length in the urban elite neighborhoods decrease the unit ridership daily bus emissions . • Future goal includes modeling the emission at stop level, in order to provide direct explanation between the type of surrounding neighborhood and ridership at each bus stop.