Analysis of Road Crash Frequency with Spatial Models (Case Study: Shiraz Metropolis): Fid-Bau Portal

Analysis of Road Crash Frequency with Spatial Models (Case Study: Shiraz Metropolis)

Sedigh Bavar, M. / Naderan, A. / Saffarzadeh, M.

The type of land use in each traffic area zone (TAZ) is the most important factor determining the number of vehicles, geometric and traffic characteristics in that zone. Any factor in the urban environment that causes congestion and attraction of vehicles at certain times increases the probability of a crash in that area. The purpose of this study is to investigate the effect of the share of different types of uses in various traffic areas of Shiraz city on the probability of a crash. The data collection of this study included 34,588 crash local bases and 37 types of land use, which were scattered in 325 TAZ. Correlation between independent variables in the model causes modeling error, so identifying the independent variables with the greatest effect in estimating the model is very important; so in this study A two-step method, including identifying the types of land uses influencing the occurrence of crashes and evaluating spatial effects between independent variables and crash data have used. In addition, the Kernel density estimate (KDE) method has also been used to find the suitable bandwidth for searching observations. In order to investigate the spatial effects of land use types on crash incidence, geographically weighted regressions (GWRs) and geographically weighted Poisson regressions (GWPRs) were used. Based on the validation criteria, the local GWPR model performs better than the global Poisson model and the local GWR model among the mentioned models. The results of the study have shown the presence of residential, commercial, barren, and abandoned uses, as well as the mixing of residential and non-residential uses. Additionally, significantly impact crashes that the large difference in the area of different types of land use in the scale of TAZ is quite noticeable on the occurrence of crashes. In some TAZ, up to 80% of the area is of one type of land use, so the correct control and management of these land uses has a greater impact on reducing crashes than other land uses.