Aspect based sentiment analysis (ABSA) involves three fundamental subtasks: aspect term extraction, opinion term extraction, and aspect-level sentiment classification. Early works only focused on solving one of these subtasks individually. Some recent work focused on solving a combination of two subtasks, e.g., extracting aspect terms along with sentiment polarities or extracting the aspect and opinion terms pair-wisely. More recently, the triple extraction task has been proposed, i.e., extracting the (aspect term, opinion term, sentiment polarity) triples from a sentence. However, previous approaches fail to solve all subtasks in a unified end-to-end framework. In this paper, we propose a complete solution for ABSA. We construct two machine reading comprehension (MRC) problems, and solve all subtasks by joint training two BERT-MRC models with parameters sharing. We conduct experiments on these subtasks and results on several benchmark datasets demonstrate the effectiveness of our proposed framework, which significantly outperforms existing state-of-the-art methods.
翻译:以视觉为基础的情绪分析(ABSA)包含三个基本子任务: 元素提取、 观点术语提取和 侧面情绪分类。 早期工作仅侧重于单个解决其中的一个子任务。 最近的一些工作侧重于解决两个子任务相结合的问题, 例如, 提取侧面术语, 以及情绪极化, 或以对称的方式提取其侧面和观点术语。 最近, 提出了三重提取任务, 即从一个句子中提取三重( 基本术语、 观点术语、 情绪极性) 。 但是, 先前的方法未能在统一的端对端框架中解决所有子任务。 在本文中, 我们为ABSA 提出了一个完整的解决方案 。 我们构建了两个机器阅读理解( MRC) 问题, 并通过两个共享参数的BERT- MRC 模型联合培训解决所有子任务 。 我们对这些子任务进行了实验, 几个基准数据集的结果显示了我们提议的框架的有效性, 大大超出现有的最新方法 。