## 4 Experiments and Results
### ICA as Fragmentation-Wave Enhancement Tool
Figures 12c, 13c and 14c show this cumulative ratio, and it can be observed that these values are lower than the twelve-lead model. The maximum values reached for each region were 0.921 in antero-septal region, 0.920 in lateral region, and 0.877 in inferior region. In the last group of experiments of this set, we tested the viability of using just the _eight mathematically independent lead_ as the input to our ICA model. An equivalent process was applied to this case as described in prior experiments. The confusion matrix for this case is presented using the kurtosis as sorting criteria in Table 7. In this experiment, the figures in the diagonal showed better performance than the twelve-lead model, moreover this case showed a 0.40 \(\epsilon_{disp}\). Finally, we measured the enhancement in fragmentation waves by using \(\rho_{RMSE}\), the ratio of fragmentation enhancement, and the ratio of cumulative fragmentation enhancement as described earlier. As it can be observed in Figure 15a, the distribution of the fragmentation wave information is spread through all the independent components, but with a much more relevant intensity in the lower components, and they present a higher number of cases with positive \(\rho_{RMSE}\). As it can be seen in Figure 15b, the shape of the distribution is similar to the twelve-lead model, but the ratio of component-by-component enhancement is much lower. Finally, Figure 15c shows the ratio of cumulative fragmentation enhancement that in this case reached the best results using four components. Table 8 \begin{table}
\begin{tabular}{c c c c c c c c c c c c} \hline \hline  & \multicolumn{4}{c}{**(a)**} & \multicolumn{4}{c}{**(b)**} & \multicolumn{4}{c}{**(c)**} \\ \hline  & **Frag 1** & **Frag 2** & **Frag 3** & **Frag 4** & **Frag 1** & **Frag 2** & **Frag 3** & **Frag 4** & **Frag 1** & **Frag 2** & **Frag 3** \\ \hline Ctrl 1 & 0.73 & 0.22 & 0.06 & 0.00 & 0.78 & 0.19 & 0.03 & 0.00 & 0.67 & 0.30 & 0.02 \\ Ctrl 2 & 0.18 & 0.66 & 0.17 & 0.00 & 0.15 & 0.67 & 0.16 & 0.01 & 0.30 & 0.64 & 0.06 \\ Ctrl 3 & 0.08 & 0.12 & 0.76 & 0.04 & 0.05 & 0.14 & 0.76 & 0.05 & 0.02 & 0.06 & 0.92 \\ Ctrl 4 & 0.01 & 0.01 & 0.02 & 0.96 & 0.01 & 0.00 & 0.05 & 0.94 & & & \\ \hline \hline \end{tabular}
\end{table} 
Table 6: Normalized confusion matrix for each heart region for ICA model, for (**a**) antero-septal, (**b**) lateral region, and (**c**) inferior region using ICA plus kurtosis. For each one, the _ij_ value of the table represents the ratio of _i_-th component of control patient that is paired with the _j_-th component of synthetically fragmented patient according to the value of PCC. shows a summary of the results, and according to the displayed figures, the best model according to the represented figures was the using the twelve-lead. Figure 12: Different measurements for the antero-septal region of the heart with ICA model. The panel (**a**) shows the distribution of \(\rho_{RMSE}\) coefficient for each independent component, values lower than zero represents cases where the RMSE measured over the ECG is greater than RMSE measured over the independent component. Panel (**b**) shows the ratio of fragmentation wave enhancement for each independent component, this ratio is computed as cases where the \(\rho_{RMSE}\) value is greater than zero. Panel (**c**) shows the cumulative ratio of fragmentation wave enhancement, this ratio is computed by joining the results of isolated independent components. Figure 13: _Cont._  
Figure 14: Different measurements for the inferior region of the heart with ICA model. (**a**) Distribution of \(\rho_{RMSE}\) coefficient for each independent component, values lower than zero represents cases where the RMSE measured over the ECG is greater than RMSE measured over the independent component. (**b**) Ratio of fragmentation wave enhancement for each independent component, this ratio is computed as cases where the \(\rho_{RMSE}\) value is greater than zero.