Search

The equitable distribution of transit services is a major concern of transportation planners and policy makers worldwide. In the United States, planners are required by executive order 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, systemwide measure that reflects the equity of transit service distribution in a metropolitan area. This measure, known as a Gini coefficient, measures specifically how well transit supply meets transit demand. Transit supply is measured with a modified form of an established supply index, and demand is estimated with population and employment data. Although the idea of a single measure for assessing the equity of a transit system is appealing, researchers and practitioners must be careful when they implement Gini coefficients for comparative purposes. This research investigated the effect of selecting various scales, boundaries, and demand measures for calculating Gini scores for interregional comparisons. Gini coefficients were calculated for six urban transit systems within two boundaries (metropolitan statistical area and transit service area) at two scales (census tract and block group) with two demand measures (population and population plus employment). Results suggest that calculations with Gini coefficients on the basis of various boundary definitions can lead to drastically different comparative results, whereas the different scales and demand measures had little impact on interregional comparisons.

The equitable distribution of transit services is a major concern of transportation planners and policy makers worldwide. In the United States, planners are required by executive order 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, systemwide measure that reflects the equity of transit service distribution in a metropolitan area. This measure, known as a Gini coefficient, measures specifically how well transit supply meets transit demand. Transit supply is measured with a modified form of an established supply index, and demand is estimated with population and employment data. Although the idea of a single measure for assessing the equity of a transit system is appealing, researchers and practitioners must be careful when they implement Gini coefficients for comparative purposes. This research investigated the effect of selecting various scales, boundaries, and demand measures for calculating Gini scores for interregional comparisons. Gini coefficients were calculated for six urban transit systems within two boundaries (metropolitan statistical area and transit service area) at two scales (census tract and block group) with two demand measures (population and population plus employment). Results suggest that calculations with Gini coefficients on the basis of various boundary definitions can lead to drastically different comparative results, whereas the different scales and demand measures had little impact on interregional comparisons.

The West African city of Accra, home to over two million of Ghana’s 25 million residents, serves as the country’s political capital and economic centre. Since gaining independence in 1957, Ghana has made significant investments in road infrastructure and services. Road transportation accounts for the majority of passenger and freight traffic in the country. This paper discusses current street design practices and some of the challenges faced by designers and residents in Accra. After providing background information on the city’s urban form, transportation system and street design agencies, case studies are conducted on three of Accra’s thoroughfares. These case studies evaluate how current design practices, based on US and British standards, meet the needs of different street users. Each of the selected roads serves a different purpose within Accra’s transportation network. The case studies revealed that pedestrians and other non-motorised transport (NMT) users are largely neglected by current design practices.