论文标题
迈向可解释的ANN:对多级多元决策树的确切转换
Towards Interpretable ANNs: An Exact Transformation to Multi-Class Multivariate Decision Trees
论文作者
论文摘要
一方面,人工神经网络(ANN)通常被标记为黑盒,缺乏可解释性。一个阻碍人类对ANN行为的理解的问题。存在一个需要生成ANN的有意义的顺序逻辑,以解释特定输出的生产过程。另一方面,决策树由于其表示语言以及有效的算法而表现出更好的解释性和表现力,将树木转化为规则。但是,基于可用数据的决策树种植可能会产生比必需的树或树木更大的树或树木,这些树或树木不太概括。在本文中,我们介绍了两种新颖的多元决策树(MDT)算法,用于从ANN中提取规则:确切可转让的决策树(EC-DT)和一种扩展的C-NET算法。他们都将具有整流线性单位激活函数的神经网络转化为代表树,可以进一步用于提取多变量规则进行推理。尽管EC-DT以层次的方式翻译ANN,以准确表示网络隐藏层隐含地学习的决策边界,但扩展的C-NET将EC-DT的分解方法与C5树学习算法相结合以形成决策规则。结果表明,尽管EC-DT在保留ANN的结构和忠诚度方面表现出色,但扩展的C-NET产生了ANN的最紧凑,最有效的树木。两种提出的MDT算法都生成规则,包括用于决策精确解释的多个属性组合。
On the one hand, artificial neural networks (ANNs) are commonly labelled as black-boxes, lacking interpretability; an issue that hinders human understanding of ANNs' behaviors. A need exists to generate a meaningful sequential logic of the ANN for interpreting a production process of a specific output. On the other hand, decision trees exhibit better interpretability and expressive power due to their representation language and the existence of efficient algorithms to transform the trees into rules. However, growing a decision tree based on the available data could produce larger than necessary trees or trees that do not generalise well. In this paper, we introduce two novel multivariate decision tree (MDT) algorithms for rule extraction from ANNs: an Exact-Convertible Decision Tree (EC-DT) and an Extended C-Net algorithm. They both transform a neural network with Rectified Linear Unit activation functions into a representative tree, which can further be used to extract multivariate rules for reasoning. While the EC-DT translates an ANN in a layer-wise manner to represent exactly the decision boundaries implicitly learned by the hidden layers of the network, the Extended C-Net combines the decompositional approach from EC-DT with a C5 tree learning algorithm to form decision rules. The results suggest that while EC-DT is superior in preserving the structure and the fidelity of ANN, Extended C-Net generates the most compact and highly effective trees from ANN. Both proposed MDT algorithms generate rules including combinations of multiple attributes for precise interpretations for decision-making.