Keyphrases
- question answering
- information extraction
- natural language processing
- question classification
- information retrieval
- named entities
- natural language
- natural language questions
- qa clef
- sentence retrieval
- cross language
- passage retrieval
- relation extraction
- open domain question answering
- syntactic information
- semantic roles
- text mining
- named entity recognition
- n gram
- answering questions
- knowledge base