## 3 Model Results for the Tested Area
### Complexity of Subsidence Causality in Alexandria  
Figure 10 illustrates the correlation coefficients for the seven models, as well as coefficients for the three potential subsidence causality factors presented in this study. The three potential causes and seven models were correlated to subsidence in the city, at the \(0.01\) level of significance. All showed positive correlation except the BL, which showed a negative correlation to subsidence with a Pearson's correlation coefficient of \(-0.121\), and a [PERSON]'s rho of \(-0.205\). For the two other individual causal factors of subsidence, FLLD had the highest positive correlation with subsidence in Alexandria, with a [PERSON]'s correlation coefficient of \(0.563\) and a [PERSON]'s rho of \(0.616\). The correlation \begin{table}
\begin{tabular}{c c c c c c} \hline \hline \multirow{2}{*}{**Former Lake/Lagoon**} & **Highest Deformation (mm/yr)** & **Lowest Deformation (mm/yr)** & **Mean Deformation (mm/yr)** & **Standard Deviation** & **Weight** \\ \hline
**Lake Alhadra** & \(0.65\) & \(-7.65\) & \(-2.45\) & \(2.08\) & \(20\) \\
**Lake Mareotis** & \(3.55\) & \(-28.15\) & \(-3.50\) & \(3.78\) & \(30\) \\
**Abu-Qir Lagoon** & \(2.37\) & \(-31.70\) & \(-6.70\) & \(5.05\) & \(45\) \\
**All FLL** & \(3.55\) & \(-31.70\) & \(-4.69\) & \(4.56\) & \(-\) \\
**No FLL** & \(3.77\) & \(-24.39\) & \(-0.53\) & \(2.36\) & \(5\) \\ \hline \hline \end{tabular}
\end{table} 
Table 3: Deformation in former lakes and lagoons dewatering (FLLD) areas of Alexandria. \begin{table}
\begin{tabular}{c c c c c c} \hline \hline  & **Highest Deformation (mm/yr)** & **Lowest Deformation (mm/yr)** & **Mean Deformation (mm/yr)** & **Standard Deviation** & **Weight** \\ \hline
**Lake Alhadra** & \(0.65\) & \(-7.65\) & \(-2.45\) & \(2.08\) & \(20\) \\
**Lake Mareotis** & \(3.55\) & \(-28.15\) & \(-3.50\) & \(3.78\) & \(30\) \\
**Abu-Qir Lagoon** & \(2.37\) & \(-31.70\) & \(-6.70\) & \(5.05\) & \(45\) \\
**All FLL** & \(3.55\) & \(-31.70\) & \(-4.69\) & \(4.56\) & \(-\) \\
**No FLL** & \(3.77\) & \(-24.39\) & \(-0.53\) & \(2.36\) & \(5\) \\ \hline \hline \end{tabular}
\end{table} 
Table 3: Deformation in former lakes and lagoons dewatering (FLLD) areas of Alexandria. coefficients for rock type show a positive correlation to subsidence with relatively lower correlation in comparison to FLLD, with a [PERSON]'s correlation coefficient of 0.337, and a [PERSON]'s rho of 0.361. Among all the processed models, the models with the highest BL rank, M5 (L\({}^{\text{-2}}\)+F\({}^{\text{1}}\)+B\({}^{\text{3}}\)), and M6 (L\({}^{\text{-1}}\)+F\({}^{\text{2}}\)+B\({}^{\text{3}}\)) show the lowest correlation coefficients. Additionally, low correlation coefficients were observed for models with low FLLD ranks, M5(L\({}^{\text{-2}}\)+F\({}^{\text{1}}\)+B\({}^{\text{3}}\)), and M3 (L\({}^{\text{-3}}\)+F\({}^{\text{1}}\)+B\({}^{\text{2}}\)). The models M1 (L\({}^{\text{-1}}\)+F\({}^{\text{1}}\)+B\({}^{\text{1}}\)), M2 (L\({}^{\text{-3}}\)+F\({}^{\text{2}}\)+B\({}^{\text{1}}\)), M4 (L\({}^{\text{-2}}\)+F\({}^{\text{3}}\)+B\({}^{\text{2}}\)), and M7 (L\({}^{\text{-2}}\)+F\({}^{\text{3}}\)+B\({}^{\text{1}}\)), had higher vertical deformation correlation coefficient values. We selected M4 (L\({}^{\text{-2}}\)+F\({}^{\text{3}}\)+B\({}^{\text{1}}\)), to model the final CSC for Alexandria, because M4 had highest correlation to subsidence, the Pearson's correlation coefficient was 0.552 in and Spearman's rho was 0.566 in. Linear regression analysis was used to correlate the model results to average vertical deformation of the city to ensure the accuracy of M4 when mapping the CSC, as shown in Figure 11, a high R\({}^{2}\) value of 0.88. confirms the applicability of this model when mapping the final CSC in Alexandria. We considered areas as stable if they did not exceed two millimeters of subsidence per year.