Keyphrases
- biomedical information retrieval
- expert search
- ranking algorithm
- information retrieval
- question answering
- test collection
- learning to rank
- web search
- ranking functions
- trec test collections
- pseudo relevance feedback
- relevance judgments
- clef ip
- resource allocation
- query expansion
- rank aggregation
- game theory
- ad hoc retrieval
- user feedback
- evaluation measures
- question answering systems
- retrieval effectiveness
- document retrieval
- search engine