Keyphrases
- question answering
- formal models
- rule based systems
- formal model
- question classification
- information retrieval
- natural language
- natural language processing
- information extraction
- process model
- answer validation
- open domain question answering
- natural language questions
- qa clef
- question answering systems
- passage retrieval
- relation extraction
- named entities
- cross language
- syntactic information
- case study
- co occurrence
- answer extraction
- knowledge representation
- answering questions
- probabilistic model
- textual entailment recognition
- artificial intelligence