## 4 Investigation and Analysis
### Analysis of Influencing Factors Based on BPNN-DEMATEL Model
(See Table 9.)  
In order to intuitively display the action relationship and evolution path of key factors, the mutual influence relationship diagram of key factors was drawn according to Table 9. The numbers on the arrows indicate the degree of influence of the key influencing factors at the tail of the arrow on the key influencing factors at the arrow point. The mutual influence relationship of \(F_{1}\), \(F_{2}\), \(F_{9}\), \(F_{14}\), and \(F_{17}\) is shown in Figure 4. According to the mutual influence and action relationship between the influencing factors, the interactive coupling between at least three factors can form a loop. In this paper, the loop formed by the three influencing factors is called the basic path, and the path formed by the interaction of the basic path and other factors is called the composite path. From Figure 4, we can find six paths, including three basic paths, including path 1: \(F_{1}\)\(\rightarrow\)\(F_{17}\)\(\rightarrow\)\(F_{14}\)\(\rightarrow\)\(F_{1}\) (0.497), path 2: \(F_{1}\)\(\rightarrow\)\(F_{9}\)\(\rightarrow\)\(F_{14}\) (0.495), and path 3: \(F_{14}\)\(\rightarrow\)\(F_{9}\)\(\rightarrow\)\(F_{2}\)\(\rightarrow\)\(F_{14}\) (0.266). There are three conforming paths, including path 4: \(F_{1}\)\(\rightarrow\)\(F_{17}\)\(\rightarrow\)\(F_{9}\)\(\rightarrow\)\(F_{14}\)  
Figure 4: The mutual influence relationship diagram of key factors in promoting prefabricated housing in Hainan Province. \begin{table}
\begin{tabular}{c c c c c c} \hline \hline \(\mathbf{Y_{5\times 5}}\) & \(\mathbf{F_{1}}\) & \(\mathbf{F_{2}}\) & \(\mathbf{F_{9}}\) & \(\mathbf{F_{14}}\) & \(\mathbf{F_{17}}\) \\ \hline \(F_{1}\) & 0.024 & 0.402 & 0.387 & 0.380 & 0.086 \\ \(F_{2}\) & 0.019 & 0.024 & 0.085 & 0.084 & 0.019 \\ \(F_{9}\) & 0.020 & 0.092 & 0.024 & 0.087 & 0.020 \\ \(F_{14}\) & 0.021 & 0.093 & 0.090 & 0.024 & 0.020 \\ \(F_{17}\) & 0.091 & 0.412 & 0.397 & 0.390 & 0.024 \\ \hline \hline \end{tabular}
\end{table} 
Table 9: Comprehensive influence matrix of key factors for promoting prefabricated housing in Hainan Province. \(F_{1}\) (0.591), path 5: \(F_{1}\to F_{17}\to F_{9}\to F_{2}\to F_{14}\to F_{1}\) (0.680), and path 6: \(F_{1}\to F_{9}\to F_{2}\to F_{14}\to F_{1}\) (0.584). From the analysis of Figure 4, we can see that the weight of the composite path is higher than that of the basic path, which means that as the interaction relationship becomes more complicated, it will cause a greater impact. (1) Evolution analysis of basic paths 1, 2, and composite path 4  
As shown in Figure 5, composite path 4 is obtained through interactive evolution based on basic path 1 and basic path 2. Specifically, for basic path 1 \(F_{1}\to F_{17}\to F_{14}\to F_{1}\) (0.497), due to imperfect standards and specifications, the design product standards are not unified, which in turn leads to insufficient market demand. For basic path 2 \(F_{1}\to F_{9}\to F_{14}\)\(\to F_{1}\) (0.495), due to imperfect standards and specifications, the enterprise lacks motivation for strategic transformation, which in turn leads to insufficient market demand. The two paths are combined to obtain composite path 4: \(F_{1}\to F_{17}\to F_{9}\to F_{14}\to F_{1}\) (0.591). Due to imperfect standards and specifications, the design product standards are not unified, which in turn leads to a lack of motivation for strategic transformation of enterprises, and ultimately insufficient market demand. (2) Evolution analysis of basic paths 1, 3, and composite path 5  
As shown in Figure 6, compound path 5 is obtained by interactive evolution based on basic path 1 and basic path 3. Specifically, for basic path 1 \(F_{1}\to F_{17}\to F_{14}\to F_{1}\) (0.497), due to imperfect standards and specifications, the design product standards are not unified, which in turn leads to insufficient market demand. For basic path 3 \(F_{14}\to F_{9}\to F_{2}\to F_{14}\) (0.266), due to insufficient market demand, the enterprise lacks motivation for strategic  
Figure 5: Composite path 4 evolution diagram.