Query Reformulation for Descriptive Queries of Jargon Words Using a Knowledge Graph based on a Dictionary

Query reformulation (QR) is a key factor in overcoming the problems faced by the lexical chasm in information retrieval (IR) systems. In particular, when searching for jargon, people tend to use descriptive queries, such as "a medical examination of the colon" rather than "colonoscopy," or they often use them interchangeably. Thus, transforming users' descriptive queries into appropriate jargon queries helps to retrieve more relevant documents. In this paper, we propose a new graph-based QR system that uses a dictionary, where the model does not require human-labeled data. Given a descriptive query, our system predicts the corresponding jargon word over a graph consisting of pairs of a headword and its description in the dictionary. First, we train a graph neural network to represent the relational properties between words and to infer a jargon word using compositional information of the descriptive query's words. Moreover, we propose a graph search model that finds the target node in real time using the relevance scores of neighborhood nodes. By adding this fast graph search model to the front of the proposed system, we reduce the reformulating time significantly. Experimental results on two datasets show that the proposed method can effectively reformulate descriptive queries to corresponding jargon words as well as improve retrieval performance under several search frameworks.