Public Transit Accessibility and Need Indices: Approaches for Measuring Service Gap

The integration of transit needs into transit accessibility indexing is important for the evaluation of existing transportation systems and, service gaps, and for the identification of priority areas for future investments in transportation infrastructure. This thesis details an accessibility-based transit need indexing model that focuses on the necessity of evaluating transit needs and transit accessibility simultaneously. A need index is developed to identify areas in high need of public transit services using economic and socio-demographic information and a composite accessibility index is developed to identify levels of access to transit services and shortcomings in service provision. The need for transit service is then modeled as the lack of transit accessibility and correlates different access indicators with their ability to predict transit service need. This model maps areas with different levels of transit accessibility and transit needs using a single score, which may be easily interpreted by planners examining transit equity. The model has been applied to Meriden and New Haven, CT and results have been compared with a general approach for consistency and effectiveness. The research also highlights the model’s usefulness as a mean to prioritize service improvement options