UCLA

The concept of accessibility has been heavily researched but slowly applied to practice. Numerous studies have shown that access to opportunities such as jobs, education, healthcare, and recreation affects people’s socio-economic wellbeing, and that low income and minority populations often suffer from poor accessibility due to lack of transportation and land use investments in their neighborhoods, as well as a lack of private transportation resources, or cars. In recent years, the state and regional governments in California are increasingly emphasizing the importance of promoting accessibility, as the concept aligns well with the state’s goal to reduce greenhouse gas emissions by encouraging denser and mixed-use urban form and discouraging car use. However, progress has been rather slow at both the regional and local levels, due to technical challenges as well as political obstacles. Moreover, while regional and local planning can promote accessibility by shaping transportation and land use investments, they have limited capacity to address the lack of transportation resources among disadvantaged populations, which is a key reason for their poor accessibility. I explore these issues in this dissertation through three separate but related essays. Essay one focuses on the potential application of accessibility metrics in local development review processes. I compare accessibility with the conventional level of service metric and California’s newly adopted vehicle miles traveled metric in evaluating transportation impacts of land use developments. I show that accessibility metrics offer a more complete and direct assessment of how land use developments affect people’s access to opportunities by a variety of travel modes. Essay two focuses on the application of accessibility in regional planning processes. I investigate how California metropolitan planning organizations use accessibility metrics to plan for long-range transportation and land use investments and prioritize investment projects (mostly transportation) for short-term implementation. I find that California MPOs use accessibility metrics more in long-range planning than near-term project prioritization and use indirect measures of accessibility more than direct measures. I also discuss major obstacles that prevent MPOs from using accessibility metrics, and one key factor that facilitates adopting accessibility. Essay three extends beyond the transportation and land use system and focuses on financial barriers to transportation access. I examine how neighborhood-level variations in auto insurance premiums may influence household car ownership, and hence contribute to accessibility disparities among different income and racial groups. I find strong associations between higher premiums and lower car ownership, and significant differences in such associations among geographic contexts, income levels, and to a limited extent, racial groups. These three essays address previously understudied topics in the literature and the findings have important implications for policy interventions to promote accessibility.