Factors affecting public transportation, car, and motorcycle usage

Document Type

Journal Article

Publication Date


Subject Area

mode - car, mode - bus, mode - bike, technology - emissions, place - asia, ridership - elasticity, ridership - mode choice, ridership - modelling


Public transportation usage, Car usage, Motorcycle usage, SURE model, CO2 emission


This study established a hypothesis model based on the seemingly unrelated regression equations (SURE) model to investigate the relationship between public transportation, car, and motorcycle use in various townships in Taiwan and to analyse important factors that affect the usage of these modes. The SURE model was adopted because of the lack of a significant correlation between the dependent variables. The pairwise covariance analysis for any two of the three transportation modes revealed that the transportation modes could substitute for one another. Factors related to modal and demographic characteristics had different impacts on the usage of the three modes. The calculation of elasticity using different population densities and public transportation usage showed that when the ‘number of city bus routes’ was increased by 50% in areas with high population density and high public transportation usage, car usage decreased by 1.4%, which corresponds to 300,000 vehicles, and total CO2 emissions reduced by 0.0204%. When the ‘total length of city bus routes’ was increased by 50%, the number of motorcycles used decreased by 83 million, and total CO2 emissions reduced by 1.119%, which corresponds to 1.4 million tonnes of CO2 emission. These findings suggest that these different factors had varying impacts on car and motorcycle usage in different areas. We therefore recommended that future transportation policies consider the varying transportation usage trends in different areas.


Permission to publish the abstract has been given by Elsevier, copyright remains with them.


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