## 4 Investigation and Analysis
### Analysis of Influencing Factors Based on BPNN-DEMATEL Model
(See Table 6.)  
\begin{table}
\begin{tabular}{c c c} \hline \hline
**Respondents** & **Number** & **Percentage** \\ \hline \multirow{4}{*}{Education} & Doctorate and above & 4 & 21.05\% \\  & Master’s degree & 8 & 42.11\% \\  & Bachelor’s degree & 6 & 31.58\% \\  & College degree and below & 1 & 5.26\% \\ \hline \multirow{4}{*}{Workplace} & Government & 5 & 26.33\% \\  & Investment and & 4 & 21.05\% \\  & development units & 3 & 15.79\% \\  & Design units & 3 & 15.79\% \\  & Construction units & 2 & 10.52\% \\  & Universities and research & 3 & 15.79\% \\  & institutes & 2 & 10.52\% \\ \hline \multirow{4}{*}{Years of working} & More than 10 years & 4 & 21.05\% \\  & 8–10 years & 6 & 31.58\% \\  & experience & 5–8 years & 7 & 36.84\% \\  & 2–5 years & 2 & 10.53\% \\ \hline \multirow{4}{*}{\(\mathbf{B}^{\prime}_{2  
horizontal axis being the centrality value (\(W_{i}\)) and the vertical axis being the causal degree value (\(R_{i}\)), as shown in Figure 3.  
As can be seen from Figure 3, the cause-effect relationship diagram was divided into four quadrants, and the influencing factors in the four areas of I, II, III, and IV were analyzed. 1. In quadrant I, factors \(F_{1}\) and \(F_{17}\) have high centrality and causality. In short, \(F_{1}\) and \(F_{17}\) are causal factors and have high importance. That is, \(F_{1}\) (imperfect standards and specifications) and \(F_{17}\) (unununified design product standards) have high centrality and causality, and their influence on other factors is greater than the influence of other factors on themselves, and they also have a greater impact on other factors. Therefore, \(F_{1}\) and \(F_{17}\) can be considered as key factors in the promotion of prefabricated housing in Hainan Province. 2. In quadrant II, factors \(F_{6}\), \(F_{12}\), \(F_{13}\), \(F_{16}\), \(F_{18}\), \(F_{19}\), and \(F_{20}\) have low centrality but high causality, that is, \(F_{6}\), \(F_{12}\), \(F_{13}\), \(F_{16}\), \(F_{18}\), \(F_{19}\), and \(F_{20}\) have low importance but are causal factors. Although \(F_{6}\) (high construction cost), \(F_{12}\) (consumers lack knowledge of prefabricated housing), \(F_{13}\) (low market recognition of prefabricated housing), \(F_{16}\) (lack of information technology application), \(F_{18}\) (enterprises lack innovation ability), \(F_{19}\) (construction units lack professional construction equipment), and \(F_{20}\) (lack of professional and technical personnel related to prefabricated housing) are of low importance, these factors have a greater impact on other influencing factors. Therefore, \(F_{6}\), \(F_{12}\), \(F_{13}\), \(F_{16}\), \(F_{18}\), \(F_{19}\), and \(F_{20}\) can be determined as key factors. 3. In quadrant III, the influencing factors \(F_{3}\), \(F_{4}\), \(F_{5}\), \(F_{8}\), \(F_{10}\), \(F_{11}\), and \(F_{15}\) have low centrality and low causality, that is, \(F_{3}\), \(F_{4}\), \(F_{5}\), \(F_{8}\), \(F_{10}\), \(F_{11}\), and \(F_{15}\) are of low importance and are result factors. These factors have a low impact on other factors and are also affected to a low degree. Therefore, \(F_{3}\), \(F_{4}\), \(F_{5}\), \(F_{8}\), \(F_{10}\), \(F_{11}\), and \(F_{15}\) can be considered non-key factors. Figure 3: Causal relationship diagram of influencing factors of prefabricated housing promotion. In quadrant IV, the influencing factors \(F_{2}\), \(F_{7}\), \(F_{9}\), and \(F_{14}\) have high centrality and low causality, and are highly important and result factors. That is, \(F_{2}\) (imperfect incentives), \(F_{7}\) (high production and transportation costs of PC components), \(F_{9}\) (lack of motivation for corporate strategic transformation), and \(F_{14}\) (lack of market demand) have high centrality and are important themselves. Moreover, \(F_{2}\) (imperfect incentives), \(F_{7}\) (high production and transportation costs of PC components), \(F_{9}\) (lack of motivation for corporate strategic transformation), and \(F_{14}\) (lack of market demand) are greatly affected by other factors.