## 3 Method
### Validation of Results
\begin{table}
\begin{tabular}{c c c c c c c c c c c c c} \hline \hline
**Functional** & **O** & **OS** & **S** & **C** & **CO** & **CS** & **R** & **RO** & **RS** & **RC** & **F** & **Total** & **UA (\%)** \\ \hline
**C** & 2 & 0 & 0 & 136 & 3 & 2 & 8 & 0 & 0 & 5 & 0 & 156 & 87.18 \\
**CO** & 0 & 0 & 1 & 2 & 28 & 0 & 1 & 0 & 0 & 0 & 2 & 34 & 82.35 \\
**CS** & 0 & 0 & 2 & 2 & 0 & 8 & 1 & 0 & 0 & 0 & 1 & 14 & 57.14 \\
**R** & 0 & 0 & 2 & 1 & 0 & 0 & 356 & 2 & 0 & 5 & 0 & 366 & 97.27 \\
**RO** & 0 & 0 & 0 & 3 & 0 & 0 & 3 & 20 & 1 & 0 & 1 & 28 & 71.43 \\
**RS** & 0 & 0 & 2 & 0 & 0 & 0 & 0 & 2 & 9 & 0 & 1 & 14 & 64.29 \\
**RC** & 0 & 0 & 0 & 1 & 0 & 0 & 4 & 0 & 0 & 69 & 0 & 74 & 93.24 \\
**F** & 0 & 0 & 1 & 0 & 0 & 0 & 4 & 0 & 0 & 0 & 29 & 34 & 85.29 \\
**Total** & 35 & 8 & 184 & 149 & 34 & 12 & 382 & 26 & 13 & 79 & 35 & 957 & \\
**PA(\%)** & 85.71 & 75.00 & 94.02 & 91.28 & 82.35 & 66.67 & 93.19 & 76.92 & 69.23 & 87.34 & 82.86 & & \\ \hline \hline \end{tabular}
\end{table} 
Table 4: _Cont._ \begin{table}
\begin{tabular}{c c c c c c c c} \hline \hline
**Method** & **Number of Samples** & **TP** & **FP** & **NP** & **Accuracy (\%)** & **Recall (\%)** & **F1 (\%)** \\ \hline Proposed method & 957 & 864 & 93 & 22 & 90.28 & 97.52 & 93.76 \\ Kernel density method [29] & 957 & 533 & 424 & 286 & 55.71 & 65.01 & 60.04 \\ Tyson polygon area share method [33] & 957 & 710 & 247 & 39 & 74.17 & 94.79 & 83.22 \\ \hline \hline \end{tabular}
\end{table} 
Table 5: Comparison of the proposed and existing methods. Figure 5: Building functional identification within Nanning Langdong Farmers’ Market according to (**a**) Gaode map, (**b**) POIs in buildings, (**c**) the proposed method, and (**d**) the kernel density method [29]. Figure 6: Cont. For buildings that do not contain POIs, the proposed method has an advantage over the Tyson polygon area share method. Figure 7 compares the building functional identification results of the proposed method and the Tyson polygon area share method at the Guangxi People's Procuratorate. This place is responsible for accepting complaints and appeals to the autonomous region's people's procuratorate and undertaking criminal complaints and state judicial assistance cases under the jurisdiction of the procuratorate. The Guangxi Procuratorate includes Buildings A and B. As shown in Figure 7b, Building A contains a public services POI and is recognised as a public services building, while Building B does not contain a POI. The proposed entity-based spatial relationship method correctly identifies the function of building B, as shown in Figure 7c. Because of the proximity of Building A to a residential neighbourhood, the Tyson polygon area share method misidentified it as residential (Figure 7d). Figure 6: Building functional identification at the Nanning People’s Hall according to (**a**) Gaode map, (**b**) POIs, (**c**) the proposed method, and (**d**) the kernel density method [29]. Figure 7: _Cont._  
Figure 8 compares the identification results for the buildings of the Nanning Daily Newspaper, which comprises buildings A, B, C, and D. As shown in Figure 8b, building A contains a public services POI and is recognised as a public services building, while buildings B, C, and D do not contain POIs. The entity spatial relationship method was used to identify that Buildings B, C, and D all have public services functions (Figure 8c). Building E is a restaurant by the gate of the Nanning Daily Newspaper and contains a commercial POI. The Tyson polygon area share method misidentifies building B as commercial (Figure 8d).