Accessibility is fundamentally thought to be related to functional, economic, and social performances of cities and geographical systems and, therefore, constitutes an essential aspect for spatial planning. Previous studies focused on cities or metropolitan scales, often disregarding their position within regional and national systems, which can greatly affect their performance. Although accessibility at various spatial scales has been examined, the studies focused on accessibility patterns at different scales, with no reference to the level of accessibility of cities over local, regional, and national scales simultaneously, i.e. multiscale accessibility. This study aims to elucidate the multiscale accessibility level of individual cities and examine its relationship to urban performance in the urban system of Israel. Spatial accessibility was analyzed using the space syntax methodology for the entire national road network across multiple geographic scales—from the local to the national scale. Based on three distinct spatial accessibility systems identified, a unique multiscale accessibility profile was created for individual cities in Israel. Subsequently, each city’s multiscale accessibility profiles were examined against urban performance indicators determined from urban scaling theory. We found that the superiority of cities characterized by high accessibility level plays a role not only for a specific scale but also over scales and spatial systems. Moreover, most urban performance indicators related to the multiscale accessibility profiles of cities, while some multiscale accessibility profiles can be related to over- or under-performance of cities. The findings suggest that pervasive accessibility across spatial scales is inherently connected to urban performance and may indicate on the implementation and interpretation of accessibility. These findings may assist in various aspects of spatial planning at various scales.

Spatial accessibility is fundamentally related to the functional, economic and social performances of cities and geographical systems and, therefore, constitutes an essential aspect for spatial planning. Despite the significant progress made in accessibility research, little attention is given to the central role of accessibility in space organization and structuration. This study aimed to fill this gap. Based on an intensive literature review, our work shows the critical role of accessibility in space organization at different scales and sizes, starting from the basic concept of accessibility and its foundations in the classical locational theories and further to the methods and theories at the forefront of research. These processes also point to a unique contribution of multiscale accessibility in space structuration. Accordingly, we offer a conceptual framework to describe the multiscale process of space structuration with respect to local-urban, regional and national scales. We believe this framework may help in studying space and, more importantly, in understanding space. We hope this perspective forms an additional tier at the conceptual and methodological levels concerning accessibility and spatial organization and will encourage empirical studies in light of the suggested view.

Accessibility is a well-known basic term in spatial science and planning and is inherently related to functional aspects of places and regions. Although previous studies have examined functional systems and spatial accessibility few have attended to the association among them across geographical scales. Our study attempts to fill this gap. Using the space syntax methodology, spatial accessibility was analyzed for the entire national road network of Israel across different geographic scales - from local culminating in the national scale. The analysis was based on angular segment analyses of the road center-line network. Following this, the correlation between spatial accessibility across scales and functional performance of employment and commuting flows was examined. The study findings show a significant correspondence and exposes transitions between local, regional and national spatio-functional systems. First, a significant correlation between local (2 km radius) accessibility levels of settlements with the number of employees and commuters. Second, the regional/metropolitan system (10-15 km radius) accessibility is highly correlated to the emergence of the main employment centers. Third, the main metropolitan areas are integrated at higher scale (from 30 km radius) and form together a core region characterized by high accessibility as well as well connectivity through commuting flows. In contrast, no substantial commuting flows were found within the periphery, as well as between periphery-core. The findings show clearly that this functional structure corresponds to the multi-scale accessibility levels of settlements. We conclude that the core region functions at multiple scales (local-regional-national) while the periphery functions mostly at a local scale.

The street network's angular centralities have been found more suitable than metric centralities for explaining the observed pedestrian and vehicle movement flows in various urban areas. Some studies relate this state to ‘network effects’ – outcomes of the underlying street network structure. However, we have yet to be ascertained how ‘network effects’ work and why angular centralities are superior to metric centralities for modeling movement in the network. The aim of this article is to clarify this issue. The investigation entailed analysis of the street network centralities and movement flows obtained through agent-based simulations conducted for two cities that differ in the pattern and size of their street networks. The findings indicate that the correlations between street network centralities and simulated movement flows, and the superiority of angular centralities in this respect, can be affected by two network's interrelated structural properties: (i) agents who calculate the shortest paths by means of metric distance pass through street segments with relatively high angular Betweenness more often than do agents who calculate the shortest paths by means of angular distance pass through street segments with a relatively high metric Betweenness; and (ii) the angular foreground sub-network (street segments in which Betweenness and Closeness values increase significantly across spatial scale) is relatively more prominent and fits the simulated movement flows better than do the metric foreground sub-networks. These structural properties are found to be nearly identical in both study cities.

This article presents a method for investigating the spatial distribution of vehicle and pedestrian traffic crashes relative to the volume of vehicle and pedestrian movement in urban areas. This method consists of two phases. First, vehicle and pedestrian traffic volumes on the street network are modeled using a space syntax configurational analysis of the network, land use data, and observed traffic data. Second, crash prediction models are fitted to the traffic crash data, using negative binomial regression models and based on traffic volume estimates and street segment lengths. The method was applied in two areas in Tel Aviv, Israel, which differ in their morphological and traffic characteristics. The case-studies illustrated the method's capability in identifying hazardous locations on the network and examining relative crash risks. The analysis shows that an increase in vehicle or pedestrian traffic volume tends to be associated with a decrease in relative crash risk. Moreover, the spatial patterns of relative crash risks are associated with the design characteristics of urban space: areas characterized by dense street networks encourage more walking, and are generally safer for pedestrians, while those with longer street segments encourage more driving, are less safe for pedestrians, but safer for vehicles.

The street network's angular properties were found more suitable than metric properties for capturing the observed pedestrian and vehicle movement flows in space syntax modeling. Some studies relat ...

Contemporary pedestrian volume models are constructed mainly within the space syntax framework with the help of Multiple Regression Analysis (MRA). Although these models predict the distribution of pedestrian volumes in the network with considerable success, they exhibit difficulties in predicting pedestrian movement in some contexts and in accounting for the combined effect of the street network structure and land-use patterns. In this paper we present an agent-based (AB) pedestrian volume model at the urban scale within the space syntax framework. The model was constructed by incorporating transformed basic components of the MRA-based space syntax model to agents' spatial behavior. The AB and MRA models were implemented in two city centers that differ in their urban growth and morphological characteristics. The suggested AB model demonstrated superiority over the MRA model in predicting pedestrian movement when the correspondence between the street network's structure, land uses and pedestrian movement was relatively low and less consistent. We attribute the superiority of the AB model to its ability to represent the combined effect of street network structure and land-use patterns on the distribution of movement flows in an urban network.