In collaboration with Payame Noor University and Iranian Geography and Urban Planning Association

Document Type : Research Paper

Authors

Abstract

Realizing structural characteristics of the urban street network has a crucial role in understanding dynamic and transforming events in a city. One of the most effective structural characteristics of street network is street network centrality which regarding former studies has a substantial effect on some events namely, distribution of activities along streets especially commercial and service activities that have a significant effect on the formation of motorized and pedestrian traffic flow throughout the city. Thus, considering street network centrality strongly improves the outcomes of urban land use and traffic planning. The current article aims at explaining the relationship between street network centrality and location selection of commercial and service activities. Firstly, it reviews key concepts related to street network centrality; specifically, focuses on metric centrality in the urban street network. Secondly, street network centrality of Qom city is modeled using Multiple Centrality Assessment (MCA) method in terms of centrality indices of intermediary, global and local closeness. Finally, datasets of street network centrality and location of activities transform to one scale unit using Kernel Density Estimation (KDE) to calculate and analyze the degree of spatial correlation between them. Correlation between mentioned variable layers is measured using Pearson’s correlation coefficient as well as spatial correlation index (SCI) which defined by the authors. Results indicate that there is a direct and high correlation between the selected street centrality indices and location selection of commercial and service activities in Qom. The highest correlation coefficients are for intermediary and local closeness centrality respectively. Global closeness centrality has the third place in terms of the correlation coefficient. As a conclusion, findings of this paper confirm that street network centrality has a significant effect on location selection of commercial and service activities in Qom city; the activities choose locations with better network centrality.

Keywords

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