Keyphrases
- question answering
- information retrieval
- natural language processing
- natural language
- information extraction
- passage retrieval
- cross language
- question classification
- named entities
- question answering systems
- qa clef
- natural language questions
- syntactic information
- textual entailment recognition
- answer extraction
- sentence retrieval
- information retrieval systems
- relevance feedback
- relation extraction
- machine learning
- candidate answers
- answer validation
- open domain question answering