Comparing similarity of concepts identified by temporal patterns of terms in biomedical research documents

In this paper, we present an analysis of a relationship between temporal trends of automatically extracted terms in medical research document and their similarities on a structured vocabulary. In order to obtain the temporal trends, we used our temporal pattern extraction method that combines an automatic term extraction, an importance index of the terms, and clustering for the values in each period. By using a set of medical research documents that were published every year, we extracted temporal patterns of the automatically extracted terms. Then, we calculated their similarities on the medical taxonomy by defining a distance on the tree structure. For analyzing the relationship between the terms included in the patterns and the similarity of the terms on the taxonomy, the differences of the averaged similarities of the terms in each pattern are compared between the two trends of the temporal patterns.