Yodan Rofè

Measuring the Gap Between Car and Transit Accessibility

Accessibility is increasingly identified in the academic literature and in planning practice as a key criterion to assess transport policies and urban land use development. This paper contributes in two respects to the growing body of literature on accessibility and accessibility measurement. First, it proposes a set of accessibility measures that directly relates transit-based and car-based accessibility to each other. Second, it presents a tool based on a geographic information system (GIS) that measures accessibility at a high level of resolution. The tool, called Urban.Access, has been developed as an ArcGIS extension and can be used in urban regions worldwide, provided high-resolution GIS data are available. Urban.Access enables a detailed representation of travel times by transit and car and thus makes it possible to adequately compare accessibility levels by transport mode. The first application of Urban.Access to the Tel Aviv, Israel, region shows substantial gaps between car-based and transit-based accessibility throughout the metropolitan area. The paper ends with a brief discussion highlighting the policy consequences of this finding.

Accessibility and Centrality for Sustainable Mobility: Regional Planning Case Study

Accessibility is a widely discussed theme, approached by several disciplines, such as geography, urban and land-use planning, and transportation. This study assesses the relevance of accessibility for sustainable mobility planning and examines the existing analogies with the concept of centrality—a consolidated issue in social science, geographic and land-use modeling, and, more recently, intensively used in social-network analysis and transport-network analysis. Centrality measures the relative importance of nodes in a network, but it can be evaluated from different perspectives. In fact, different indexes are available to measure different ways for a node to be central. This paper also examines recent innovations in accessibility modeling and suggests improvement by proposing a new accessibility measure. This paper uses both traditional and lesser-known measures to analyze a case study, considering both accessibility and centrality indexes with the aim of investigating their potential correlation, efficacy, and suitability to support an integrated land-use and transport-planning approach.

The impact of planning on pedestrian movement: contrasting pedestrian movement models in pre-modern and modern neighborhoods in Israel

Most pedestrian movement volume models were constructed for urban areas that developed on the basis of pre-modern planning. In this paper, we confront neighborhoods that were built upon modern planning doctrines, combining the functional hierarchy of streets with the neighborhood unit concept, with neighborhoods that developed from pre-modem non-hierarchical street-based planning. We use space syntax analysis to investigate how their street network’s structural attributes interact with pedestrian movement distribution. The investigation was conducted in 14 neighborhoods from 4 cities in Israel by examining the correlation of observed pedestrian volume with models using different axial- and segment-based topological, angular, and metric syntactic attributes across different radii (scales). The results indicate that the street network and the distribution of pedestrian movement interact differently in the two neighborhood types. In pre-modern neighborhoods: (i) there is significantly more walking; (ii) the street network’s syntactic attributes tend to be much more consistent in their correlation with pedestrian volume across all scales; (iii) the correlation of pedestrian volume with these attributes and with commerce is relatively high; and (iv) pedestrian movement distribution is more predictable. We relate these differences to the absence of a self-organized circular causality between street network structure, commerce, and movement in modern planned neighborhoods.

The benefits of a high-resolution analysis of transit accessibility

ABSTRACT Accessibility is an important consideration in sustainable mobility policies, particularly for transit users. Measures suggested in the literature are based on coarse aggregate spatial resolution of traffic analysis zones that is sufficient for managing car travels only. To reflect a human door-to-door travel, transit accessibility demands an explicit view of the location of origin, transit stops and destination, as well as of the temporal fit between transit lines timetable and traveler’s needs. We thus estimate transit accessibility based on mode-specific travel times and corresponding paths, including walking and waiting, at the resolution of individual buildings and stops. Car accessibility is estimated at a high resolution too. A novel representation of transit network as a graph is proposed. This representation includes all modal components of a transit travel – walking, waiting at a stop, transit ride, transfers between lines, thus enabling unified view of a travel, regardless of mode. The use of modern high-performance graph database allows construction of high-resolution accessibility maps for an entire metropolitan area with its 100–200 K buildings. The application is tested and applied in a case study involving the evaluation of the 2011 bus line reform in the city of Tel Aviv. Specifically, we demonstrate that while the reform increased the average accessibility for the entire city the increase was not uniform with different areas of the city experiencing different absolute accessibility by transit and relative accessibility in comparison to car travel. The bus reform did in fact benefit travelers that experienced low relative accessibility, but the benefits are mainly accruing to longer trips. Our approach and computational methods can be employed for directly investigating the impacts of transportation infrastructure investments.

Estimation of Urban Transport Accessibility at the Spatial Resolution of an Individual Traveler

Accessibility, particularly for public transport users is an important consideration in sustainable mobility policies. Various accessibility measures have been suggested in the literature, most at coarse aggregate spatial resolution of zones or neighborhoods. Based on recently available Big Urban GIS data our aim is to measure accessibility from the viewpoint of an individual traveler who traverses the transportation network from one building as origin to another at the destination. We estimate transport accessibility by car and by public transport based on mode-specific travel times and corresponding paths, including walking and waiting. A computational application that is based on the intensive querying of relational database management systems is developed to construct high-resolution accessibility maps for an entire metropolitan area. It is tested and implemented in a case study involving the evaluation of a new light rail line in the metropolitan area of Tel Aviv. The results show essential dependence of accessibility estimates on spatial resolution—high-resolution representations of the trip enable unbiased estimates. Specifically, we demonstrate that the contribution of the LRT to accessibility is overrated at low resolutions and for longer journeys. The new approach and fast computational method can be employed for investigating the distributional effects of transportation infrastructure investments and, further, for interactive planning of the urban transport network.