1 Integrated approach to mode choice including environmental concern and acceptability of bus service priority: A comparative study between Japan and Indonesia

Travel mode choice of commuters between private vehicle and public transit represents a conflict known as a social dilemma. While TDM strategies to cope with social dilemmas assume to affect people ’s travel decision, the acceptance of TDM measures is influenced by the psychological factor of environmental concern and awareness. The paper focuses on the acceptability of bus priority measures and pres ents an integrated choice and latent variable model. We conducted case studies in two local cities of Niigata, Japan and Yogyakarta, Indonesia to compare the importance of psychological factors affecting mode choice between private car and bus. In Niigata, Japan, the study focused employees working in the central area and commuting by car from the suburban areas. A path diagram of the structural equation model (SEM) shows that fundamental environmental concern influences on the direct factors of ‘expectation of modal shift ‘ and ‘justice and endurance of bus priority’, and the direct factors contribute to the ‘acceptance of bus priority’. Promotion of fundamental environmental concern as well as reflection on the impact of automobile dependency is required to accept bus priority measures. The integrated choice and latent variable model reveals that attitudinal and awareness promotion of bus priority contributes to modal shift into bus. In Yogyakarta, Indonesia, the study also focused on employees and students living in the suburbs and commuting to the central area by car. Its SEM reveals that fundamental environmental concern influences neither on the expectation of modal shift, nor on the justice and endurance of bus priority measures. Car-commuters are asking to provide better level of service such as a comfortable air-conditioned vehicle to change into bus use, but psychological factors such as environmental concern and acceptance of bus priority measures do not influence on modal choice