| # DermAssist – ResNet50 Ensemble | |
| ## Model Overview | |
| DermAssist is a dermoscopic skin lesion malignancy risk estimation model built using a 3-model ResNet50 ensemble. | |
| The system outputs: | |
| - Malignancy probability | |
| - Confidence score | |
| - Uncertainty estimation (ensemble disagreement) | |
| This model is designed for dermoscopic image triage workflows. | |
| --- | |
| ## Architecture | |
| Backbone: | |
| ResNet50 (ImageNet pretrained) | |
| Classifier Head: | |
| Linear → ReLU → Dropout (0.5) → Linear → 1 output logit | |
| Training Details: | |
| - Optimizer: AdamW (lr = 1e-4, weight_decay = 1e-4) | |
| - Loss: BCEWithLogitsLoss (class-weighted) | |
| - Early Stopping: Validation AUC | |
| - Full fine-tuning applied | |
| Ensemble Strategy: | |
| Three independently trained models. | |
| Final probability = mean prediction. | |
| Uncertainty = standard deviation across models. | |
| --- | |
| ## Performance | |
| ### Internal Validation (HAM10000) | |
| | Metric | Value | | |
| |--------|-------| | |
| | AUC-ROC | 0.937 | | |
| | Accuracy | 0.86 | | |
| | Malignant Recall | > 0.90 | | |
| | Malignant Precision | ~0.52 | | |
| | Benign Precision | ~0.96 | | |
| --- | |
| ### External Validation (ISIC 2019 – Filtered Classes) | |
| | Metric | Value | | |
| |--------|-------| | |
| | AUC-ROC | ~0.72 | | |
| | Accuracy | ~0.57 | | |
| Observed performance variation reflects dataset distribution differences. | |
| --- | |
| ## Intended Use | |
| This model is intended for: | |
| - Dermoscopic image triage | |
| - Educational experimentation | |
| - Ensemble uncertainty analysis | |
| - Explainability demonstration | |
| This model is not intended for autonomous medical diagnosis. | |
| --- | |
| ## Limitations | |
| - Trained on dermoscopic images only | |
| - Binary mapping reduces lesion taxonomy complexity | |
| - Sensitive to dataset distribution shift | |
| - Requires calibrated threshold tuning | |
| --- | |
| ## Files in Repository | |
| - resnet50_model_1.pth | |
| - resnet50_model_2.pth | |
| - resnet50_model_3.pth | |
| All three models are required for ensemble inference. | |
| --- | |
| ## Ethical Considerations | |
| AI-based medical systems must be used responsibly. | |
| This model does not replace dermatologist evaluation. |