KDEIR at CLEF eHealth 2016: Health Documents Re-ranking Based on Query Variations

In this paper, we describe our participation in the CLEF eHealth 2016 task 3: Patient-Centred Information Retrieval focusing on the clinical web documents based on user queries in the health forum. In our participation, we submitted three runs in ad-hoc search and two runs in query variation search subtasks. In ad-hoc search, the main challenge is to retrieve high quality clinical documents based on user query. For ad-hoc search, we employ multiple features based unsupervised reranking method to the documents retrieved by a baseline system. During the query variation search, the main challenge is to generate a ranked list of documents covering the different variations of the query. To tackle the query variation problem, first we formulate a query and a set of information needs from the query variation. Then, we re-rank the documents retrieved for the formulated query by focusing on the set of information needs.