This paper introduces a methodological approach for evaluating transportation-based access via the public roadway network referred to as edge accessibility, which is derived from the graph theory measure of closeness. EA evaluates each edge in the roadway network based on its system-wide contribution in facilitating access between all origin-destination (OD) pairs in the roadway network and includes an edge disruption component in the calculation. The measure also includes an importance weighting approach that can be applied to both origins and destinations to addresses concerns related to equity and criticality and can be readily incorporated into existing transportation planning models. The measure is demonstrated via a case study that examines food accessibility by socially vulnerable populations in a rural setting to support the expansion of a fixed-route public transit service. As part of the case study, authors use a statewide network of all public roadways in a GIS-based transportation planning platform called TransCAD™, a customizable off-the-shelf software for transportation network applications.
