Improving the Usefulness of Decision Trees as Explanations

Jiří Němeček · Tomáš Pevný · Jakub Marecek

Video

Paper PDF

Thumbnail of paper pages

Abstract

In classification with tabular data, one often utilizes tree-based models. Those can be competitive with deep neural networks on tabular data and, under some conditions, explainable. The explainability depends on the tree's depth and the accuracy of each leaf. Decision trees containing leaves with unbalanced accuracy can provide misleading explanations. Low-accuracy leaves provide less useful explanations to the individuals they classify. Here, we train a shallow tree that minimizes the maximum misclassification error across leaf nodes. The shallow tree provides a more useful global explanation, while its overall statistical performance can approach that of state-of-the-art methods by extending the leaves with additional models, creating a partially interpretable model.