Keyphrases
- question answering
- passage retrieval
- natural language processing
- information extraction
- named entities
- natural language
- question classification
- candidate answers
- cross language
- natural language questions
- relation extraction
- question answering systems
- syntactic information
- feature weighting
- qa clef
- information retrieval
- tf idf
- semantic roles
- qa systems
- sentence retrieval
- wordnet
- answering questions