Rough co‐citation as a measure of relationship to expand co‐citation networks for scientific paper searches

Abstract

ABSTRACTThis paper proposes a “rough co‐citation”, which is a measure of relationship to expand co‐citation networks so as to include new relevant documents. A rough co‐citation relationship is a linkage between a pair of documents which are cited by two other documents in a similar citation context. The linkage strength of a rough co‐citation relationship may be weaker than the original co‐citation relationship, because a rough co‐citation relationship is determined by citations in two separate documents. Rough co‐citation linkages, however, may yield new relevant documents that are not identified by the original co‐citation linkages. For example, the rough co‐citation can identify relevant documents that are published after the citing document of the original co‐citation becomes public. This study conducted IR experiments to evaluate the search performances of retrieval methods using the co‐citation networks expanded by the rough co‐citation relationships. Specifically, the random walk with restart, which is one of the latest graph search algorithms, is applied to the expanded and original co‐citation networks. Scores of the normalized discounted cumulative gain (nDCG@K) are then compared. The results indicate that the search performance of the method using the expanded network outperforms a baseline method using the original network.