Changing Effects of Job Accessibility on Employment and Commute: A Case Study of Los Angeles

Accessibility has become a key indicator to evaluate performance of transportation plans and policies. Nevertheless, empirical evidence of the effects of accessibility is inconclusive. The mixed results raise questions about the significance of space and require examining the constancy of job accessibility's effects over time. This research investigates the effects on worker-to-population ratios and commute time between 1990 and 2007-2011 in the Los Angeles metropolitan area using spatial regression models and interactive dummy variables. The results show that higher job accessibility is significantly associated with shorter commute time, and the association between job accessibility and worker-to-population ratios is weak and even insignificant. Moreover, the effects of job accessibility did not significantly change between 1990 and 2007-2011 but fluctuated in between.