Advancing the practice of regional transportation equity analysis: a San Francisco bay area case study

Abstract

As the transportation industry continues to evolve, it is urgent that we develop and implement methods for clearly evaluating the range of transportation engineering, planning, and policy impacts experienced by various population segments. While theories of transportation equity have advanced over the past decade, such advancements outpace existing methods for evaluating the fairness of large-scale transportation investments for disadvantaged communities. In this study, a regional activity-based travel model for the Bay Area, California is used to perform an equity analysis of two of the region’s transportation and land-use planning scenarios. Equity outcomes are tested relative to three equity standards: Equality, Proportionality, and Rawlsian justice. The primary objective is to demonstrate the usefulness of a full-scale activity-based travel model for regional transportation equity analysis. We demonstrate that fine-grained distributional measures play an important role in examining the individual and household-level impacts of regional transportation scenarios, and can complement existing Environmental Justice assessments and equity analyses by helping to explain underlying reasons for average group impacts. Distributional measures can further reveal harmful cases when disadvantaged groups are most likely to experience the disbenefits of the transportation scenarios. Yet, each type of measures in isolation does not tell the complete story of which planning scenario is likely to deliver more equitable outcomes. Finally, we demonstrate the significance of applying equity standards for ranking planning scenarios, and we find that the ranking of scenarios will vary according to the equity standard, as well as how associated evaluation criteria are defined.

Evaluating spatial inequity in last-mile delivery: a national analysis

“…Since line-haul distances constitute a substantially higher proportion of total VMT, the evaluation compares percent differences between the two scenarios rather than raw VMT savings. Moreover, comparing individual difference densities grants nuanced insights into the distribution of impacts across target/control groups (Bills, 2022; Bills and Walker, 2017).…”

“…Recent transportation planning literature, however, has adopted more nuanced, liberal egalitarian arguments (Pereira et al ., 2017). For instance, Bills (2022) calculate individual difference densities in logsum accessibility—a relative, distribution-based indicator—to evaluate proportional and Rawlsian equity in proposed transportation improvements in the San Francisco Bay Area. Nahmias-Biran and Shiftan (2020) draw on a Capabilities Approach (CA) to transport, which centers freedom of choice and well-being over need-based access to resources, and derive a value of capabilities metric that monetizes accessibility gains, which can then input into conventional cost-benefit analyses.…”

Different journeys, same struggle: Practitioner experiences in environmental justice policy, assessment, and decision-making

“…Qualitative data underwent an initial round of open, descriptive coding with reliability increased through the development of a codebook (Bazeley, 2013;Saldaña, 2016). Codes and themes were formed, arranged, and validated through the constant comparative method throughout the data analysis process as new data was compiled (Glaser, 1965).…”