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Unformatted text preview: At a higher level phrases
and sentences have to be parsed, semantically interpreted and integrated. Finally
the required pieces of information like "position" and "incoming person name"
are entered into the database. Although the most accurate information extraction
systems often involve handcrafted language-processing modules, substantial
progress has been made in applying data mining techniques to a number of
3.3.1 Classiﬁcation for Information Extraction Entity extraction was originally formulated in the Message Understanding
Conference (Chinchor 1997). One can regard it as a word-based tagging
problem: The word, where the entity starts, get tag "B", continuation words get
tag "I" and words outside the entity get tag "O". This is done for each type of
entity of interest. For the example above we have for instance the person-words
"by (O) John (B) J. (I) Donner (I) Jr. (I) the (O)".
Hence we have a sequential classiﬁcati...
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This note was uploaded on 06/19/2011 for the course IT 2258 taught by Professor Aymenali during the Summer '11 term at Abu Dhabi University.
- Summer '11