Different ways to get to the same workplace: How does workplace location relate to commuting by different income groups?

We examine whether commonly-observed differences in commute behavior among different income groups are associated with the location of their workplaces. Using the Chicago metropolitan area as a case study, we classify six types of workplace locations to reflect the degree of employment centralization versus decentralization and the degree of employment clustering versus dispersion. Based on the 2008 Chicago Regional Household Travel Inventory, we found that low-income workers are more likely to work in centralized but dispersed workplaces, while high-income workers are more likely to work in employment clusters. The unequal distribution of workers in different workplaces, combined with distinctive commuting patterns to certain workplaces, partly explains commonly-observed commute differences, such as shorter-distance commutes and more public transit use by lower-income workers. Regression analysis shows that the association between income and commute mode varies by workplace, and, more importantly, commute mode has a greater association with workplace locations than with income. The results suggest considering workplace locations in empirical research on commuting inequalities and when establishing transportation and housing policies.