## 4 Results
### Analysis of the Results  
In this section, the final results were analyzed. Average and minimum methods were chosen. Regarding the choice of the minimum method, we consider that the HVR is a constantly changing process over a specific time, and the influencing factors affecting housing vacancy are also complex. The HVR will be inflated at different times. Therefore, the minimum value was chosen to observe and analyze the change in housing vacancy. The average method, which is often used in the characterization of the object of study, such as air temperature. The researchers represent the average temperature of the day by calculating the average of each time point. This method was referred to compare it with the minimum method to find the HVR calculation method that is closest to the real situation. The results are as follows:  
Figures 7 and 8 show the calculated results of HVR. The spatial distribution of vacant houses can be seen in Figure 7, with clear transition zones. From Figure 8, we can see a clear high value area and low value area, while the part directly between high and low values is not obvious. In the final field verification of the main urban area of Xi'an city, it is found that the HVR results obtained by the average method are closer to the actual results. Therefore, the results were further analyzed in accordance with Figure 8.  
Figure 6: House vacancy rate at different times: (**a**) 19 August 2018; (**b**) 23 August 2018; (**c**) 31 October 2018; (**d**) 11 March 2019. The results of HVR were grouped by districts, and the average HVR of each district was obtained, which can be seen in Figure 9.  
Figure 8: Minimum values of the house vacancy rates in Xi’an city. Figure 7: Average house vacancy rates in Xi’an city. As the iconic old town of Xi'an city, The average HVR of Beilin District was 0.043. Beilin District is named after the well-known \"Forest of Steles in Xi'an\", at home and abroad, which is an urban area with a developed culture and education system, cultural relics and scenic spots, strong scientific and technological projects, and a prosperous market economy. There are more employment opportunities in urban areas and the various basic service facilities are of high quality; thus, the HVR in Beilin District was lower than that in other urban areas. The average HVR in Yanta District was 0.079. The data show that in 2021, the sales area for commercial housing in Yanta District reached 3.731 million square meters, accounting for 20.1% of the total sales area of Xi'an city. Having the largest GDP in Xi'an city, Yanta District is the jurisdiction where many organs are located as well as the jurisdiction with news media such as television stations and key reception venues. The infrastructure and living facilities in Yanta District are of high quality, and 162 municipal roads and five subway lines have jointly formed an efficient and convenient three-dimensional transportation network. Therefore, the overall HVR in Yanta District was low, and the utilization of housing was in good condition. The average HVR in Lianhu District was 0.129. As the largest ethnic minority settlement in the city, Lianhu District has 43 ethnic minorities, mainly concentrated on the 2.3 square kilometer Beiyuanmen Historical and Cultural Block within the Ming City Walls. Lianhu District has significant locational advantages, with more than 25,000 commercial outlets, Star Hotel accounts for 30% of Xi'an city, and a high-quality traffic road network. As a key area for transformation and development, its purpose is to form a new pattern of linked developments for various areas in the district. The HVR increased significantly compared with Yanta District and Beilin District, and the housing use situation was better since Lianhu District is in the process of comprehensive transformation from the old city to a new urban area. The average HVR in Weiyang District was 0.151.