Supervised Feature Compression based on Counterfactual Analysis
This work addresses the need for interpretable AI models in domains requiring transparency, though it is incremental as it builds on existing counterfactual explanation methods.
The paper tackles the problem of making black-box models interpretable by using counterfactual explanations to identify important decision boundaries, which then guide a supervised discretization of features to train compact, interpretable decision trees. Numerical results on real-world datasets demonstrate effectiveness in terms of accuracy and sparsity.
Counterfactual Explanations are becoming a de-facto standard in post-hoc interpretable machine learning. For a given classifier and an instance classified in an undesired class, its counterfactual explanation corresponds to small perturbations of that instance that allows changing the classification outcome. This work aims to leverage Counterfactual Explanations to detect the important decision boundaries of a pre-trained black-box model. This information is used to build a supervised discretization of the features in the dataset with a tunable granularity. Using the discretized dataset, an optimal Decision Tree can be trained that resembles the black-box model, but that is interpretable and compact. Numerical results on real-world datasets show the effectiveness of the approach in terms of accuracy and sparsity.