A desirable property of learning systems is to be both effective and interpretable. Towards this goal, recent models have been proposed that first generate an extractive explanation from the input text and then generate a prediction on just the explanation called explain-then-predict models. These models primarily consider the task input as a supervision signal in learning an extractive explanation and do not effectively integrate rationales data as an additional inductive bias to improve task performance. We propose a novel yet simple approach ExPred, that uses multi-task learning in the explanation generation phase effectively trading-off explanation and prediction losses. And then we use another prediction network on just the extracted explanations for optimizing the task performance. We conduct an extensive evaluation of our approach on three diverse language datasets -- fact verification, sentiment classification, and QA -- and find that we substantially outperform existing approaches.
翻译:学习系统的可取属性是既有效又可解释的。为了实现这一目标,最近的一些模型已经提出,首先从输入文本中产生一个解析性解释,然后对所谓的解释性当时的预测性模型作出预测。这些模型主要将任务投入视为学习解析性解释的监督信号,而没有有效地将理由数据作为提高任务绩效的另外一种诱导性偏差加以整合。我们提出了一个创新而简单的方法ExPred,在解释性生成阶段采用多重任务学习,有效地交换解释性和预测性损失。然后我们利用另一个关于只提取的解释的预测网络来优化任务绩效。我们广泛评价了我们关于三种不同语言数据集的方法 -- -- 事实核实、情绪分类和QA -- -- 并发现我们大大超越了现有方法。