CRFClassifier is a Java implementation of a Named Entity Recognizer.
Named Entity Recognition (NER) labels sequences of words in a text which are
the names of things, such as person and company names, or gene and
protein names.
The software provides a general (arbitrary order) implementation of linear chain
Conditional Random Field (CRF)
sequence models, coupled with well-engineered feature
extractors for Named Entity Recognition.
(CRF models were pioneered by
Lafferty,
McCallum, and Pereira (2001); see
Sutton
and McCallum (2006) for a better introduction.)
Included with the download are good 3 class
(PERSON, ORGANIZATION, LOCATION) named entity recognizers for English (in
versions with and
without additional distributional similarity features) and another pair
of models trained on the
CoNLL 2003
English training data. The
distributional similarity features improve performance but the models
require considerably more memory.
