Keyphrases
- question answering
- information retrieval
- test collection
- question classification
- qa systems
- information extraction
- question answering systems
- open domain question answering
- retrieval effectiveness
- clef ip
- qa clef
- natural language
- question answer
- machine learning
- answer extraction
- open domain
- blog opinion retrieval
- cross language
- pseudo relevance feedback
- information access
- information retrieval systems
- ir evaluation
- evaluation campaigns
- co occurrence
- relevance feedback
- neural network