# How Does the Built Environment Affect Mechanical Parking Space Planning: A Case Study in Xi'an City
## 4 Study Area and Data  
The study area is the center city of Xi'an, Shannxi province. Xi'an land space overall planning (2021-2035) ([[http://zygh.xa.gov.cn/web_files/zygh/file/2022/11/08/2022110](http://zygh.xa.gov.cn/web_files/zygh/file/2022/11/08/2022110)]([http://zygh.xa.gov.cn/web_files/zygh/file/2022/11/08/2022110](http://zygh.xa.gov.cn/web_files/zygh/file/2022/11/08/2022110)) 81852155156437.pdf, accessed on 4 April 2024) defined the central urban area of Xi'an is about 766 square kilometers, including seven districts. The total number of parking lots is 2506, of which 216 have mechanical parking spaces. In order to explore the influence of built environment factors on mechanical parking spaces and provide a theoretical basis for the construction of mechanical parking lots, this study selected the proportion of the mechanical parking spaces ratio as the dependent variable, and the range of independent variables is [0, 1]. A value of 0 means that all parking spaces are ordinary parking spaces, 0.5 indicates that mechanical parking spaces account for 50% of the total parking spaces, and 1 indicates that all parking spaces are mechanical parking spaces. The distribution of parking lots (yellow dots) and parking lots including mechanical parking spaces (red dots) in the center city of Xi'an are shown in Figure 1.  
Figure 1: The distribution of parking lots. The survey data of parking lots in Xi'an obtained in this study include the basic characteristics of parking lots, such as latitude and longitude coordinates, number of parking spaces and mechanical parking spaces, cost, and architecture type. The analysis of spatial data must take into account the scale effect and the zoning effect. In order to analyze the built environment around the parking lots, it is necessary to choose the appropriate size of the analysis unit. The whole modeling process requires that the spatial analysis unit should not be too large in order to ensure the validity of the measurement of the built environment on the one hand and to highlight the intrinsic variability of the factors of the built environment on the other hand. In reference to the selection of buffer zones in the study on the built environment and motor vehicle travel behavior [34], this paper finally selects the 500 m buffer zone of the parking lots as the research unit. Ten indicators were selected from the \"7D\" system to construct the independent variable system. Three parking lot characteristic indicators are cost, area, and architecture type. The open source population density raster data are obtained from the World Population Data website ([[https://hub.worldpop.org/](https://hub.worldpop.org/)]([https://hub.worldpop.org/](https://hub.worldpop.org/)) (accessed on 20 May 2024)); Point of Interest (POI) data are obtained using the Python program, which is used to access the Gaud API to crawl, and the coordinate transformation plug-in of ArcGIS 10.2 is used to transform the GCJ-02 coordinate system of Gaud into the WGS-84 coordinate system; the road network data intercepts the road network within the scope of the study through the open source map website (OpenStreetMap, OSM) and converts the dual-line road network into a single-line network. The dual-line roads specify the direction of vehicle travel. For an intersection, there is one intersection regardless of the number of lanes. Without this treatment, multiple intersections are counted based on lane crossings. The Kolmogorov-Smirnov test (K-S test) is a non-parametric hypothesis test in statistics that is used to test whether a single sample follows a certain distribution or whether two samples follow the same distribution. The K-S test can not only assess the degree of fit of the sample data to the theoretical distribution, which can help us to better understand the characteristics and regularity of the data distribution, but also determine whether the distribution of features is the same in the training set and the test set. If the K-S test value is greater than 0.05, the data follow a normal distribution.