CitationLDA++: an Extension of LDA for Discovering Topics in Document Network

Along with rapid development of electronic scientific publication repositories, automatic topics identification from papers has helped a lot for the researchers in their research. Latent Dirichlet Allocation (LDA) model is the most popular method which is used to discover hidden topics in texts basing on the co-occurrence of words in a corpus. LDA algorithm has achieved good results for large documents. However, article repositories usually only store title and abstract that are too short for LDA algorithm to work effectively. In this paper, we propose CitationLDA++ model that can improve the performance of the LDA algorithm in inferring topics of the papers basing on the title or/and abstract and citation information. The proposed model is based on the assumption that the topics of the cited papers also reflects the topics of the original paper. In this study, we divide the dataset into two sets. The first one is used to build prior knowledge source using LDA algorithm. The second is training dataset used in CitationLDA++. In the inference process with Gibbs sampling, CitationLDA++ algorithm use topics distribution of prior knowledge source and citation information to guide the process of assigning the topic to words in the text. The use of topics of cited papers helps to tackle the limit of word co-occurrence in case of linked short text. Experiments with the AMiner dataset including title or/and abstract of papers and citation information, CitationLDA++ algorithm gains better perplexity measurement than no additional knowledge. Experimental results suggest that the citation information can improve the performance of LDA algorithm to discover topics of papers in the case of full content of them are not available.