Implicit feature identification in Chinese reviews using explicit topic mining model

The essential work of feature-specific opinion mining is centered on the product features. Previous related research work has often taken into account explicit features but ignored implicit features, However, implicit feature identification, which can help us better understand the reviews, is an essential aspect of feature-specific opinion mining. This paper is mainly centered on implicit feature identification in Chinese product reviews. We think that based on the explicit synonymous feature group and the sentences which contain explicit features, several Support Vector Machine (SVM) classifiers can be established to classify the non-explicit sentences. Nevertheless, instead of simply using traditional feature selection methods, we believe an explicit topic model in which each topic is pre-defined could perform better. In this paper, we first extend a popular topic modeling method, called Latent Dirichlet Allocation (LDA), to construct an explicit topic model. Then some types of prior knowledge, such as: must-links, cannot-links and relevance-based prior knowledge, are extracted and incorporated into the explicit topic model automatically. Experiments show that the explicit topic model, which incorporates pre-existing knowledge, outperforms traditional feature selection methods and other existing methods by a large margin and the identification task can be completed better.