A quantitative approach for the comparison of additive local explanation methods

Local additive explanation methods are increasingly used to understand the predictions of complex Machine Learning (ML) models. The most used additive methods, SHAP and LIME, suffer from limitations that are rarely measured in the literature. This paper aims to measure these limitations on a wide range (304) of OpenML datasets using six quantitative metrics, and also evaluate emergent coalitional-based methods to tackle the weaknesses of other methods. We illustrate and validate results on a specific medical dataset, SA-Heart. Our findings reveal that LIME and SHAP's approximations are particularly efficient in high dimension and generate intelligible global explanations, but they suffer from a lack of precision regarding local explanations and possibly unwanted behavior when changing the method's parameters. Coalitional-based methods are computationally expensive in high dimension, but offer higher quality local explanations. Finally, we present a roadmap summarizing our work by pointing out the most appropriate method depending on dataset dimensionality and user's objectives.(c) 2023 Elsevier Ltd. All rights reserved.

Automated summary

This paper aims to evaluate the limitations of the widely used additive explanation methods, SHAP and LIME, on a wide range of datasets and propose coalitional-based methods to overcome their weaknesses. The results show that SHAP and LIME are efficient in generating intelligible global explanations in high dimension, but they lack precision in local explanations and may exhibit unwanted behavior when changing parameters. Coalitional-based methods are computationally expensive but offer higher quality local explanations. A roadmap is provided to guide the selection of the most appropriate method based on dataset dimensionality and user's objectives.