Date of Completion
Dr. Carol Atkinson-Palombo, Dr. Karthik Konduri
Field of Study
Master of Science
The equitable distribution of transit services is a major concern of transportation planners and policymakers worldwide. In the US, planners are required by law to consider equity concerns when investing in new transportation infrastructure and services. However, equity can be difficult to assess in a consistent, objective, and quantitative way. Australian researchers recently developed a single, system wide measure which reflects the horizontal (or spatial) equity of transit service distribution in a metropolitan area. This measure, a variation of the Gini coefficient, specifically measures how well transit supply meets transit demand. While using a single measure to assess the equity of a transit system is very appealing, researchers must be very careful when implementing Gini coefficients for comparative purposes. This research investigates the effect of using different scales, levels of data resolution, and various demand measures when calculating Gini scores for interregional comparisons. Gini coefficients are calculated for six urban transit systems at two scales (metropolitan statistical area and transit service area) and two levels of resolution (census tract and block group) using two different demand measures (population and population plus employment). The results suggest that calculating Gini coefficients at different scales can lead to drastically different comparative results, while the different levels of resolution and demand measures had very little impact on interregional comparisons. This research also explores the possibility of using Gini coefficients to assess vertical equity by using poverty data to estimate demand.
Bertolaccini, Kelly L., "Assessing the Equity of Transit Supply Distribution in Metropolitan Areas Using Lorenz Curves and Gini Coefficients" (2013). Master's Theses. 483.
Dr. Nicholas E. Lownes