## 3 Experimental Results
### Investigation of Critical Frequency Bands
\begin{table}
\begin{tabular}{c c c c c c c c} \hline \hline \multirow{2}{*}{**Feature**} & \multirow{2}{*}{**Classifier**} & \multicolumn{3}{c}{**Valence**} & \multicolumn{3}{c}{**Arousal**} \\ \cline{3-8}  & & **Precision** & **Recall** & **F1** & **Precision** & **Recall** & **F1** \\ \hline \multirow{3}{*}{**PSD**} & **NB** & 60.51/6.71 & 56.65/4.99 & 48.84/9.54 & 57.54/6.15 & 54.95/4.29 & 46.86/8.54 \\  & **SVM** & 69.04/5.91 & 65.62/6.55 & 65.24/7.39 & 68.60/8.07 & 61.09/6.17 & 60.41/7.47 \\  & **LORSAL** & 63.29/6.54 & 62.15/6.65 & 61.84/7.27 & 61.62/6.64 & 59.02/5.53 & 58.46/6.54 \\ \hline \multirow{3}{*}{**DE**} & **NB** & 61.04/5.76 & 60.31/5.19 & 58.83/5.48 & 58.46/5.00 & 58.96/5.05 & 55.84/5.74 \\  & **SVM** & 69.55/6.58 & 66.93/6.50 & 66.89/7.15 & 69.92/7.94 & 63.50/6.57 & 63.45/7.54 \\  & **LORSAL** & **77.17/6.37** & **76.79/6.21** & **76.90/6.27** & **77.03/6.20** & **76.15/6.14** & **76.47/6.14** \\ \hline \multirow{3}{*}{**DASM**} & **NB** & 62.36/5.66 & 62.18/5.54 & 61.73/5.57 & 60.34/4.50 & 60.79/4.90 & 59.76/4.77 \\  & **SVM** & 64.48/10.21 & 63.01/7.15 & 62.01/9.11 & 61.79/12.34 & 59.06/6.36 & 57.49/8.46 \\  & **LORSAL** & 71.63/4.94 & 71.38/4.92 & 71.43/4.92 & 71.20/4.96 & 70.68/5.00 & 70.82/4.94 \\ \hline \multirow{3}{*}{**RASM**} & **NB** & 55.65/6.77 & 53.72/4.64 & 46.01/7.92 & 53.57/4.25 & 52.38/2.95 & 40.70/6.37 \\  & **SVM** & 48.17/17.72 & 52.47/5.24 & 43.24/9.56 & 43.46/15.61 & 50.25/0.98 & 40.00/3.72 \\  & **LORSAL** & 51.67/7.53 & 51.35/2.98 & 46.69/5.49 & 50.67/8.33 & 50.60/2.11 & 45.32/3.94 \\ \hline \multirow{3}{*}{**DCAU**} & **NB** & 61.95/5.52 & 61.65/5.44 & 61.26/5.48 & 59.98/4.50 & 60.14/4.50 & 59.36/4.37 \\  & **SVM** & 63.48/9.93 & 62.09/6.51 & 60.99/8.59 & 60.04/12.79 & 58.21/6.32 & 56.12/8.76 \\ \cline{1-1}  & **LORSAL** & 69.89/4.89 & 69.68/4.77 & 69.71/4.81 & 68.48/4.93 & 68.11/4.90 & 68.19/4.88 \\ \hline \hline \end{tabular}
\end{table} 
Table 3: The mean metrics and standard deviations (%) of precision, recall, and F1 for the binary classification of LV/HV and LA/HA emotions obtained by the compared classifiers for different features extracted the total frequency bands. respectively. Thus, \(F_{n}(L,H)\) indicates the class separability between emotions L and H for the \(n\)-th dimension of the extracted feature. Figure 4: Effects of the different frequency bands (Delta, Theta, Alpha, Beta, Gamma, and Total) on the classification precisions for LV/HV emotions obtained by the LORSAL, SVM, and NB classifiers for the five different features: (**a**) PSD, (**b**) DE, (**c**) DASM, (**d**) RASM, (**e**) DCAU. Figure 5: Effects of the different frequency bands (Delta, Theta, Alpha, Beta, Gamma, and Total) on the classification precisions for LA/HA emotions obtained by the LORSAL, SVM, and NB classifiers for the five different features: (**a**) PSD, (**b**) DE, (**c**) DASM, (**d**) RASM, (**e**) DCAU. Given the extracted feature and the specific frequency bands, the mean Fisher ratio \(F(\mathrm{L},\mathrm{H})\) is calculated by averaging the values of \(F_{n}(\mathrm{L},\mathrm{H})\) over all the EEG channels (e.g., PSD and DE) or combinations of electrodes (e.g., DASM, RASM, and DCAU)  
\[F(\mathrm{L},\mathrm{H})=\frac{1}{N}\sum_{n=1}^{N}F_{n}(\mathrm{L},\mathrm{H}), \tag{12}\]  
where \(N\) is the number of EEG channels or combinations of electrodes. Figure 6 shows the Fisher ratio of the extracted PSD, DE, DASM, RASM, and DCAU feature along different frequency bands by averaging the values over all subjects in valence and arousal dimensions, respectively. In addition, Table 4 illustrates the Fisher ratio over different frequency bands by averaging the values over all features and subjects in valence and arousal dimensions, respectively. The Fisher ratio values shown in Table 4 are calculated by further averaging the values presented in Figure 6 over the five different frequency bands.