Incorporating and measuring social equity in transit service allocation

Abstract

Transit accessibility is evaluated against theories of equity and social justice. Legal and ideological justifications are used to establish a baseline of "who matters" in equity analyses. A generalizable methodology for calculating accessibility using the general transit feed specification (GTFS) is established and demonstrated. The analysis finds that aggregating various socio-economic and demographic factors into a single index masks relationships between accessibility and each individual factor. For transit services operated by King County Metro in Washington State, a strong, positive relationship is found between accessibility and decreasing income. No significant relationship is found between accessibility and minority populations. A strong, negative relationship is found between accessibility and disabled populations. It is argued that Metro's policies governing the allocation of fixed-route transit service should account for people with disabilities. Drawing upon various theories of equity, a framework for evaluating the equity of disparities in accessibility between groups is proposed.