From Entity Recognition to Entity Linking: A Survey of Advanced Entity Linking Techniques

Abstract

Several research results have showed that finding information about certain entities is the most common information needs of information retrieval users. The needs should be answered by returning specific entities, their properties or related concepts instead of just any type of documents. While some search engines are capable of recognizing specific types of entities, true entity-oriented search still has a long way to go because of the high ambiguity in names across documents. Entity linking (EL) goes beyond the entity recognition task by linking a textual named entity mention to a knowledge base entry. It is a difficult task involving several challenges. This paper gives a complete survey of the EL task in the general and the biomedical domain and points out several unexplored challenges found in the EL task.