The lack of interpretability remains a barrier to the adoption of deep neural networks. Recently, tree regularization has been proposed to encourage deep neural networks to resemble compact, axis-aligned decision trees without significant compromises in accuracy. However, it may be unreasonable to expect that a single tree can predict well across all possible inputs. In this work, we propose regional tree regularization, which encourages a deep model to be well-approximated by several separate decision trees specific to predefined regions of the input space. Practitioners can define regions based on domain knowledge of contexts where different decision-making logic is needed. Across many datasets, our approach delivers more accurate predictions than simply training separate decision trees for each region, while producing simpler explanations than other neural net regularization schemes without sacrificing predictive power. Two healthcare case studies in critical care and HIV demonstrate how experts can improve understanding of deep models via our approach.

本文介绍了一种名为“地区树规则化”的方法，它可以在维持准确率的同时让神经网络更具有可解释性，该方法通过预先定义输入空间中特定区域所需的决策逻辑，鼓励深层模型分别被数个分离的决策树所逼近，本方法在多个数据集上都比只训练每个区域的决策树更能提高准确预测，同时比其他神经网络规则化方案更简单，并不会破坏预测能力；两个医疗案例证明了本方法可以通过对神经网络的审查来提高理解。

区域树正则化用于黑盒模型的可解释性