Difference between revisions of "Part-of-speech tagging"

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{{TOCD}}
'''Part-of-speech tagging''' is the process of assigning unambiguous grammatical categories<ref>Also referred to as "parts-of-speech"</ref> to words in context. The crux of the problem is that [[surface form]]s of words can often be assigned more than one part-of-speech by [[morphological analysis]]. For example in English, the word "trap" can be both a singular noun ("a trap") or a verb ("I'll trap it").
 
   
 
'''Part-of-speech tagging''' is the process of assigning unambiguous grammatical categories<ref>Also referred to as "parts-of-speech", e.g. Noun, Verb, Adjective, Adverb, Conjunction, etc.</ref> to words in context. The crux of the problem is that [[surface form]]s of words can often be assigned more than one part-of-speech by [[morphological analysis]]. For example in English, the word "trap" can be both a singular noun ("a trap") or a verb ("I'll trap it").
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This page intends to give an overview of how part-of-speech tagging works in Apertium, primarily within the <code>apertium-tagger</code>, but giving a short overview of constraints (as in [[constraint grammar]]) and restrictions (as in <code>apertium-tagger</code>) as well.
   
 
==Hidden Markov Models==
 
==Hidden Markov Models==
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==Training==
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===Expectation-Maximisation (EM)==
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===Baum-Welch===
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==Tagging==
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===Viterbi===
   
 
==Notes==
 
==Notes==

Revision as of 09:30, 3 September 2008

Part-of-speech tagging is the process of assigning unambiguous grammatical categories[1] to words in context. The crux of the problem is that surface forms of words can often be assigned more than one part-of-speech by morphological analysis. For example in English, the word "trap" can be both a singular noun ("a trap") or a verb ("I'll trap it").

This page intends to give an overview of how part-of-speech tagging works in Apertium, primarily within the apertium-tagger, but giving a short overview of constraints (as in constraint grammar) and restrictions (as in apertium-tagger) as well.

Hidden Markov Models

Training

=Expectation-Maximisation (EM)

Baum-Welch

Tagging

Viterbi

Notes

  1. Also referred to as "parts-of-speech", e.g. Noun, Verb, Adjective, Adverb, Conjunction, etc.