Causes of transportation inequality: The case of bike sharing in the U.S.

The bike-sharing system, as an innovation to solve the first-and-last-mile transportation problem, tends to be disproportionally used much less by lower income users. In this paper, we focus on testing two causes of this inequality: availability of stations and affordability, using a difference-in-difference framework with various treatments. We discovered that stations are more readily available in higher-income areas. However, increasing station availability will not reduce the usage inequality. Instead, we find that equity programs that increase the affordability of low-income users can reduce the usage gap between high and low-income groups. The major findings of this paper suggest that to create a more inclusive and equal urban transportation ecosystem, urban planners, policymakers, and bike-sharing operators need to allocate more resources to support affordability.