Two-Step Multi-Factor Attention Neural Network For Answer Selection

Attention-based neural network models recently proposed have achieved great success in question answering task. They focus on introducing the interaction information in sentence modeling rather than representing the question and the answer individually. However, there are some limitations of the previous work. First, in the interaction layer, most attention mechanisms do not make full use of the diverse semantic information of the question. Second, they have limited capability to construct interaction from multiple aspects. In this paper, to address these two limitations, we propose a two-step multi-factor attention neural network model. The two-step strategy encodes the question into different representations according to separate words in the answer, and these representations are employed to build dynamic-question-aware attention. Additionally, a multi-factor mechanism is introduced to extract various interaction information, which aims at aggregating meaningful facts distributed in different matching results. The experimental results on three traditional QA datasets show that our model outperforms various state-of-the-art systems.