Resumen
The cities of developing countries are undertaking implementation of rail based transit systems, especially metro rail, as a solution to the problems of urban traffic congestion and rapidly increasing travel demand, keeping in view the goal of sustainable development. Traffic congestion mainly finds its roots in the ever increasing number of private vehicles, which in turn is primarily attributed to low levels of service provided by existing public transport. After the introduction of metro system, however, an analysis as to whether the system has been successful in veering the masses away from their private modes and onto the new metro mode is of crucial importance. This paper presents such an investigation on the mode shifting behavior towards a newly operational metro rail mode in Mumbai city, India, so as to understand the key tangibles perceived most important by the end user responsible for the mode shift. The investigation involves designing, implementing and analyzing Revealed and Stated Preference questionnaire surveys. The Revealed Preference (RP) survey has been conducted on commuters using the newly operational metro rail line which has provided the much needed east-west connectivity in Mumbai city, whereas an appropriately designed Stated Preference (SP) experiment has been administered on the commuters living within the catchment of a proposed additional metro rail line. The RP and SP datasets collected are used for estimating econometric mode choice models by analyzing the combined dataset using the sequential estimation method. Separate models are estimated for private vehicle users and public transit users. Before the development of a combined RP and SP model of mode choice, a discrete choice model using only the RP data explaining the mode shift behavior of commuters of new metro rail is developed and presented. The RP survey shows approximately 80% of respondents were using public transport even before shifting to the new metro line, whereas approximately 60% of the respondents from SP survey who are currently using private vehicle show willingness to shift to the proposed metro rail line, showing the need for the metro rail alignment along the corridor. Results of this analysis have been used in updating parameters of existing transportation planning model and estimation of ridership on the proposed transit system along the new corridor, and realistically determining the value commuters assign to travel time savings and comfort inside transit vehicles.