Keyphrases
- question answering
- information retrieval
- natural language processing
- natural language
- question classification
- question answering systems
- open domain question answering
- information extraction
- passage retrieval
- syntactic information
- cross language
- answer validation
- qa clef
- machine learning
- natural language questions
- sentence retrieval
- named entities
- relation extraction
- candidate answers
- semantic roles
- answering questions
- data mining