Assessing the social costs of public transport in a mixed traffic environment with endogenous demand

In reality, public transport (PT) passenger demand levels are influenced by internal factors rather than external ones, as they are shaped by the performance of public transport services such as price, service frequency and travel time. This paper develops a calculation process for PT endogenous demand with respect to social costs in motorcycle-dominated mixed transport systems, based on the total social cost of public transport in previous research. The incremental elasticity analysis is used to estimate the endogenous passenger demand for dedicated PT technologies. A case study of Quang Trung – Tran Phu – Nguyen Trai corridor in Hanoi is presented, highlighting the incremental elasticity analysis (IEA) of PT modes, including conventional buses,bus rapid transit (BRT), monorail and urban rail transit (URT), with a focus on passenger waiting and invehicle times. The findings reveal that conventional buses are most cost-effective for daily demands below 31,000 passengers per direction per day (pdd), while BRT is preferable for demands ranging from 31,000 to 55,000 pdd. The Monorail emerges as the most efficient option for demand between 55,000 and 165,000 pdd, with Urban Rail Transit (URT) becoming optimal when demand exceeds 165,000 pdd. These insights provide urban transport planners and policymakers with valuable guidance for strategic decision-making regarding new PT projects in mixed transport environments with a dominance of motorcycles