Keyphrases
- noun phrases
- finite state transducers
- n gram
- part of speech
- finite state
- language modeling
- named entities
- machine translation
- semantic relations
- language model
- query translation
- keywords
- pseudo relevance feedback
- query terms
- grammatical inference
- query expansion
- question answering
- markov chain
- information retrieval
- hidden markov models
- expert systems
- pattern recognition
- database systems