## 4 Results and Discussion
### Risk Interdependency Model in Rock
Regarding the risk interdependency model of the cost of pile installation, DR and OGR directly affect the cost. On the other hand, the SR and EQR risk groups indirectly affect the cost through DR. For example, the risk of soil type (SR2) plays an essential role in the risk of the distance between the pile and an adjacent pile (DR7) and on the length and diameter of the pile concrete (DR8). In addition, there is a risk due to the size limitation of the equipment (SR3) on the length and diameter of the concrete pile (DR8). The rankings of the significant time risks for pile installation in sand and rock were compared and are shown in Figure 7a,b, respectively. Management risks are essential to the time needed to construct a pile in sand via MR1 and MR2, while MR1 and MR3 are crucial time risks for constructing a pile in rock. In addition, the most relevant risk groups for sand are construction risks (CR4 and CR6) and owner-generated risks (OGR2 and OGR3), as shown in Figure 7a. On the other hand, the essential risk groups for rock are economic risks (ECR1, ECR7, and ECR3) and owner-generated risks (OGR2 and OGR4), as shown in \begin{table}
\begin{tabular}{c c c c c c c c c c c} \hline \hline  & \multicolumn{4}{c}{**Time**} & \multicolumn{4}{c}{**Cost**} \\ \hline  & **DR** & **ECR** & **EAR** & **MR** & **OGR** & **DR** & **EAR** & **OGR** & **SR** \\ \hline DR & 0.752 & & & & DR & 0.754 & & & \\ ECR & 0.150 & 0.714 & & & EAR & 0.218 & 0.689 & & \\ EAR & 0.204 & 0.111 & 0.745 & & & OGR & 0.203 & 0.098 & 0.747 & \\ MR & 0.156 & 0.141 & 0.086 & 0.724 & & SR & 0.208 & 0.034 & 0.051 & 0.742 \\ OCR & 0.209 & 0.182 & 0.064 & 0.110 & 0.727 & & & & & \\ \hline \hline \end{tabular}
\end{table} 
Table 13: Discriminant validity in terms of Fronell–Larcker. \begin{table}
\begin{tabular}{c c c c c c c c c c c} \hline \hline  & \multicolumn{4}{c}{**Time**} & \multicolumn{4}{c}{**Cost**} \\ \hline  & **DR** & **ECR** & **EAR** & **MR** & **OGR** & **DR** & **EAR** & **OGR** & **SR** \\ \hline DR7 & 0.630 & 0.073 & 0.115 & 0.050 & 0.138 & DR7 & 0.701 & 0.136 & 0.156 & 0.069 \\ DR8 & 0.857 & 0.143 & 0.184 & 0.165 & 0.175 & DR8 & 0.804 & 0.188 & 0.152 & 0.232 \\ ECR1 & 0.145 & 0.790 & 0.117 & 0.160 & 0.150 & EQR1 & 0.197 & 0.927 & 0.105 & 0.048 \\ ECR3 & 0.061 & 0.630 & 0.033 & 0.028 & 0.108 & EQR2 & 0.077 & 0.300 & \(-\)0.007 & \(-\)0.032 \\ EQR4 & 0.149 & 0.056 & 0.732 & 0.056 & 0.064 & OGR1 & 0.148 & 0.028 & 0.610 & \(-\)0.001 \\ EQR7 & 0.156 & 0.107 & 0.759 & 0.072 & 0.032 & OGR4 & 0.160 & 0.105 & 0.862 & 0.064 \\ MR1 & 0.131 & 0.136 & 0.072 & 0.831 & 0.090 & SR2 & 0.161 & 0.039 & 0.030 & 0.768 \\ MR3 & 0.091 & 0.058 & 0.051 & 0.599 & 0.068 & SR3 & 0.148 & 0.010 & 0.046 & 0.714 \\ OCR2 & 0.145 & 0.141 & 0.046 & 0.117 & 0.766 & & & & & \\ OCR4 & 0.159 & 0.124 & 0.047 & 0.038 & 0.685 & & & & & \\ \hline \hline \end{tabular}
\end{table} 
Table 14: Discriminant validity in terms of cross-loading. Figure 7b. Based on these risk groups, the results provided by the time risk interdependency model in rock agreed with the results of the study by [PERSON] and [PERSON] (2016), in which OGR, ECR, and DR are the significant risk groups for pile installation time, as shown in Figure 7c. Figure 6: Risk interdependency models for the (**a**) time and (**b**) cost of pile installation in rock. \begin{table}
\begin{tabular}{c c c c c c c c} \hline \hline  & \multicolumn{3}{c}{**Time**} & \multicolumn{3}{c}{**Cost**} \\ \hline
**Path** & **b** & **t Value** & _p-Value_ & **Path** & **b** & **t Value** & _p-Value_ \\ \hline DR \(\rightarrow\) TIME & 0.139 & 1.898 & 0.058 & DR \(\rightarrow\) COST & 0.374 & 2.095 & 0.037 \\ ECR \(\rightarrow\) TIME & 0.111 & 1.873 & 0.062 & EQR \(\rightarrow\) DR & 0.211 & 1.713 & 0.087 \\ EQR \(\rightarrow\) DR & 0.193 & 1.966 & 0.050 & OGR \(\rightarrow\) Cost & 0.166 & 2.368 & 0.018 \\ MR \(\rightarrow\) DR & 0.139 & 1.689 & 0.092 & SR \(\rightarrow\) DR & 0.201 & 2.587 & 0.010 \\ OGR \(\rightarrow\) ECR & 0.182 & 2.261 & 0.024 & & & \\ \hline \hline \end{tabular}
\end{table}