  Mobility resilience refers to the ability of individuals to complete their
desired travel despite unplanned disruptions to the transportation system. The
potential of new on-demand mobility options, such as ridesourcing services, to
fill unpredicted gaps in mobility is an underexplored source of adaptive
capacity. Applying a natural experiment approach to newly released ridesourcing
data, we examine variation in the gap-filling role of on-demand mobility during
sudden shocks to a transportation system by analyzing the change in use of
ridesourcing during unexpected rail transit service disruptions across the
racially and economically diverse city of Chicago. Using a multilevel mixed
model, we control not only for the immediate station attributes where the
disruption occurs, but also for the broader context of the community area and
city quadrant in a three-level structure. Thereby the unobserved variability
across neighborhoods can be associated with differences in factors such as
transit ridership, or socio-economic status of residents, in addition to
controlling for station level effects. Our findings reveal that individuals use
ridesourcing as a gap-filling mechanism during rail transit disruptions, but
there is strong variation across situational and locational contexts.
Specifically, our results show larger increases in transit disruption
responsive ridesourcing during weekdays, nonholidays, and more severe
disruptions, as well as in community areas that have higher percentages of
White residents and transit commuters, and on the more affluent northside of
the city. These findings point to new insights with far-reaching implications
on how ridesourcing complements existing transport networks by providing added
capacity during disruptions but does not appear to bring equitable gap-filling
benefits to low-income communities of color that typically have more limited
mobility options.
