XAI Method

Characteristics

Description of Pneumonia CXR Image

Spatial Resolution

LIME

*A method of approximating the prediction result of a black box model with another model.

*Approximate classifiers are not always correct.

*Multiple lesions (GGO, consolidation, etc.) in the image can be effectively visualized.

*Highlight which superpixel region of the image is most important for classification.

*The spatial resolution is adjusted according to the number of superpixels, allowing for a high degree of flexibility in feature investigation.

Occlusion Sensitivity

*A method of making data partially obstructive and measuring the importance of a region using a black box model.

*The importance of combination features cannot be expressed.

*Multiple lesions (GGO, consolidation, etc.) in the image can be visualized.

*Highlight which region of the image is most important for classification.

*The spatial resolution is adjusted according to the mask size and the size of the stride, allowing for a high degree of flexibility in feature investigation.

Grad-CAM

*A method to make the black box model itself have an evidence for judgment.

*Describes the regions that affects the final score.

*Focuses on a wide range of a major lesion and therefore cannot identify (visualize) multiple lesions in the image [26] .

*Highlight the pixels that contribute to change the final decision.

*The spatial resolution of the feature map in the final convolution layer is low because it is 7 × 7 (in the case of ResNet-50).