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Performance analysis of different feature selection methods
| Methods | Accuracy (%) | Precision (%) | Recall (%) | F1-score (%) | Specificity (%) |
|---|---|---|---|---|---|
| Kvasir-V1 | |||||
| OOA | 94.17 | 94.54 | 93.92 | 94.23 | 92.67 |
| COA | 96.66 | 95.15 | 95.38 | 95.27 | 94.38 |
| BES | 97.37 | 95.12 | 96.30 | 95.71 | 94.79 |
| SOA | 97.99 | 96.53 | 97.98 | 97.25 | 96.95 |
| ESOA | 99.60 | 99.20 | 98.71 | 98.96 | 99.88 |
| Kvasir-V2 | |||||
| OOA | 94.26 | 94.65 | 93.33 | 94.65 | 93.33 |
| COA | 95.58 | 95.21 | 94.67 | 95.21 | 94.67 |
| BES | 97.51 | 95.18 | 96.84 | 95.18 | 96.84 |
| SOA | 97.51 | 97.18 | 96.84 | 97.18 | 96.84 |
| ESOA | 99.88 | 99.61 | 97.12 | 99.61 | 97.12 |
| HyperKvasir | |||||
| OOA | 94.32 | 94.78 | 93.85 | 94.11 | 92.91 |
| COA | 96.28 | 95.42 | 95.16 | 95.29 | 94.63 |
| BES | 97.14 | 95.88 | 96.41 | 96.14 | 95.37 |
| SOA | 97.92 | 96.71 | 97.65 | 97.18 | 96.82 |
| ESOA | 99.74 | 99.33 | 98.95 | 99.14 | 99.61 |
Performance analysis of different classification methods
| Methods | Accuracy (%) | Precision (%) | Recall (%) | F1-score (%) |
|---|---|---|---|---|
| Kvasir-V1 | ||||
| RNN | 89.44 | 90.51 | 88.90 | 91.42 |
| GRU | 93.80 | 94.03 | 93.59 | 92.14 |
| LSTM | 96.04 | 95.99 | 94.88 | 94.66 |
| Stacked-LSTM | 99.60 | 98.71 | 99.88 | 99.20 |
| Kvasir-V2 | ||||
| RNN | 90.56 | 90.50 | 91.27 | 92.95 |
| GRU | 94.07 | 93.10 | 92.00 | 94.56 |
| LSTM | 97.49 | 96.40 | 95.55 | 95.61 |
| Stacked-LSTM | 99.88 | 97.93 | 97.12 | 99.61 |
| HyperKvasir | ||||
| RNN | 89.88 | 90.65 | 89.44 | 91.12 |
| GRU | 93.92 | 94.21 | 93.78 | 92.83 |
| LSTM | 96.38 | 96.10 | 95.21 | 95.68 |
| Stacked-LSTM | 99.74 | 98.95 | 99.33 | 99.14 |
Performance analysis of computational complexity across datasets
| Methods | Datasets | Memory consumption (MB) | Training time (s) | Inference time (s) |
|---|---|---|---|---|
| RNN | Kvasir-V1 | 27.12 | 37.95 | 36.74 |
| GRU | 23.05 | 32.58 | 30.84 | |
| LSTM | 8.67 | 30.58 | 26.59 | |
| Stacked-LSTM-SAF | 6.72 | 2.54 | 9.58 | |
| RNN | Kvasir-V2 | 27.48 | 38.62 | 37.12 |
| GRU | 22.87 | 35.12 | 31.04 | |
| LSTM | 9.02 | 31.28 | 27.11 | |
| Stacked-LSTM-SAF | 6.58 | 2.73 | 9.92 | |
| RNN | HyperKvasir | 30.48 | 42.69 | 40.98 |
| GRU | 27.46 | 25.96 | 22.02 | |
| LSTM | 21.69 | 19.78 | 17.36 | |
| Stacked-LSTM-SAF | 8.46 | 5.80 | 11.96 | |
Comparative analysis of existing methods on Kvasir-V1 and V2 datasets
| Methods | Datasets | Accuracy (%) | Precision (%) | Recall (%) | F1-score (%) |
|---|---|---|---|---|---|
| LPNet [17] | Kvasir-V1 | 93.55 | 93.55 | 93.55 | 93.55 |
| VGG16 kernle RBF [19] | Kvasir-V2 | 96.64 | 97 | 97 | 97 |
| SK-Net [20] | Kvasir-V1 | 98.45 | N/A | 96.60 | N/A |
| Kvasir-V2 | 97.83 | N/A | N/A | N/A | |
| Star-GAN + InceptionNet-V3 [21] | Kvasir-V2 | 94.96 | N/A | 94.93 | 94.93 |
| CapsNet [22] | Kvasir-V2 | 93.40 | N/A | N/A | N/A |
| Proposed ESOA with Stacked LSTM-SAF | Kvasir-V1 | 99.60 | 98.71 | 99.88 | 99.20 |
| Kvasir-V2 | 99.88 | 97.93 | 97.12 | 99.61 |
Cross-dataset validation results: Trained on Kvasir-V1 and tested on Kvasir-V2
| Methods | Accuracy (%) | Precision (%) | Recall (%) | F1-score (%) |
|---|---|---|---|---|
| RNN | 87.35 | 88.20 | 86.50 | 87.34 |
| GRU | 91.12 | 92.05 | 90.50 | 91.27 |
| LSTM | 94.50 | 95.10 | 93.80 | 94.44 |
| Stacked LSTM-SAF | 97.25 | 96.80 | 96.00 | 96.39 |
Performance analysis of different activation functions
| Methods | Accuracy (%) | Precision (%) | Recall (%) | F1-score (%) | T-test from p-values | CI (%) |
|---|---|---|---|---|---|---|
| Kvasir-V1 | ||||||
| Stacked LSTM-ReLU | 94.97 | 93.47 | 92.60 | 93.63 | 0.032 | 86.18 |
| Stacked LSTM-Tanh | 95.46 | 93.28 | 94.30 | 95.04 | 0.030 | 87.63 |
| Stacked LSTM-Sigmoid | 97.03 | 96.96 | 95.43 | 96.01 | 0.029 | 89.06 |
| Stacked LSTM-sech | 99.50 | 98.71 | 99.88 | 99.20 | 0.026 | 94.12 |
| Kvasir-V2 | ||||||
| Stacked LSTM-ReLU | 93.55 | 92.53 | 92.67 | 91.76 | 0.034 | 89.60 |
| Stacked LSTM-Tanh | 96.62 | 95.71 | 96.00 | 97.26 | 0.030 | 90.17 |
| Stacked LSTM-Sigmoid | 97.45 | 95.50 | 94.18 | 96.65 | 0.028 | 91.78 |
| Stacked LSTM-sech | 99.88 | 97.93 | 97.12 | 99.61 | 0.024 | 94.36 |
| HyperKvasir | ||||||
| Stacked LSTM-ReLU | 94.76 | 93.62 | 92.89 | 93.45 | 0.036 | 87.15 |
| Stacked LSTM-Tanh | 95.84 | 94.71 | 95.25 | 95.07 | 0.034 | 89.36 |
| Stacked LSTM-Sigmoid | 97.28 | 96.64 | 95.81 | 96.22 | 0.031 | 91.58 |
| Stacked LSTM-Sech | 99.74 | 98.95 | 99.33 | 99.14 | 0.029 | 94.85 |