An index to measure accessibility poverty risk

Over the past decade, a range of measures and indicators has been developed to assess accessibility disparities among divergent population groups in a metropolitan region. This chapter adds to this body of literature by presenting an accessibility index that can be easily used to assess and rank metropolitan regions based on the overall level of equity of a region's transport system. In the chapter, we discuss the rationale of the index, discuss its properties, and apply it to the Rotterdam-The Hague metropolitan area in the Netherlands. We start with the definition of accessibility poverty, which refers to a situation of low accessibility that severely restricts a person's ability to participate in the activities deemed normal in a particular society. Drawing on the indices to measure income poverty, we define an accessibility poverty risk index, which takes into account both the intensity of accessibility poverty (How low is the accessibility level experienced by people?) and the extent of accessibility poverty (How many people are affected by accessibility poverty?). The application to the Rotterdam-The Hague region shows, perhaps against expectations, that (sub)urban areas contribute most to the overall accessibility poverty risk in the region. We end with a discussion on how the accessibility poverty risk index can be employed in the practice of transport planning and project appraisal.