  Transportation equity advocates recommend improving public transit in
low-income neighbourhoods to alleviate socio-spatial inequalities and increase
quality of life. However, transportation planners often overlook transit
investments in neighbourhoods with "transit-captive" populations because they
are assumed to result in less mode-shifting, congestion relief, and
environmental benefits, compared to investments that aim to attract choice
riders in wealthier communities. In North American cities, while many
low-income households are already transit users, some also own and use private
vehicles. It suggests that transit improvements in low-income communities could
indeed result in more transit use and less car use. Accordingly, the main
objective of this article is to explore the statistical relationship between
transit use and transit accessibility as well as how this varies by household
income and vehicle ownership in the Greater Toronto and Hamilton Area (GTHA).
Using stratified regression models, we find that low-income households with one
or more cars per adult have the most elastic relationship between transit
accessibility and transit use; they are more likely to be transit riders if
transit improves. However, we confirm that in auto-centric areas with poor
transit, the transit use of low-income households drops off sharply as car
ownership increases. On the other hand, a sensitivity analysis suggests more
opportunities for increasing transit ridership among car-deficit households
when transit is improved. These findings indicate that improving transit in
low-income inner suburbs, where most low-income car-owning households are
living, would align social with environmental planning goals.
