| .. Copyright (C) 2001-2024 NLTK Project |
| .. For license information, see LICENSE.TXT |
|
|
| .. -*- coding: utf-8 -*- |
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|
| ========================= |
| Word Sense Disambiguation |
| ========================= |
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| Lesk Algorithm |
| -------------- |
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| Performs the classic Lesk algorithm for Word Sense Disambiguation (WSD) using |
| a the definitions of the ambiguous word. |
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| Given an ambiguous word and the context in which the word occurs, Lesk returns |
| a Synset with the highest number of overlapping words between the context |
| sentence and different definitions from each Synset. |
|
|
| >>> from nltk.wsd import lesk |
| >>> sent = ['I', 'went', 'to', 'the', 'bank', 'to', 'deposit', 'money', '.'] |
|
|
| >>> print(lesk(sent, 'bank', 'n')) |
| Synset('savings_bank.n.02') |
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|
| >>> print(lesk(sent, 'bank')) |
| Synset('savings_bank.n.02') |
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|
| The definitions for "bank" are: |
|
|
| >>> from nltk.corpus import wordnet as wn |
| >>> for ss in wn.synsets('bank'): |
| ... print(ss, ss.definition()) |
| ... |
| Synset('bank.n.01') sloping land (especially the slope beside a body of water) |
| Synset('depository_financial_institution.n.01') a financial institution that accepts deposits and channels the money into lending activities |
| Synset('bank.n.03') a long ridge or pile |
| Synset('bank.n.04') an arrangement of similar objects in a row or in tiers |
| Synset('bank.n.05') a supply or stock held in reserve for future use (especially in emergencies) |
| Synset('bank.n.06') the funds held by a gambling house or the dealer in some gambling games |
| Synset('bank.n.07') a slope in the turn of a road or track; the outside is higher than the inside in order to reduce the effects of centrifugal force |
| Synset('savings_bank.n.02') a container (usually with a slot in the top) for keeping money at home |
| Synset('bank.n.09') a building in which the business of banking transacted |
| Synset('bank.n.10') a flight maneuver; aircraft tips laterally about its longitudinal axis (especially in turning) |
| Synset('bank.v.01') tip laterally |
| Synset('bank.v.02') enclose with a bank |
| Synset('bank.v.03') do business with a bank or keep an account at a bank |
| Synset('bank.v.04') act as the banker in a game or in gambling |
| Synset('bank.v.05') be in the banking business |
| Synset('deposit.v.02') put into a bank account |
| Synset('bank.v.07') cover with ashes so to control the rate of burning |
| Synset('trust.v.01') have confidence or faith in |
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| Test disambiguation of POS tagged `able`. |
|
|
| >>> [(s, s.pos()) for s in wn.synsets('able')] |
| [(Synset('able.a.01'), 'a'), (Synset('able.s.02'), 's'), (Synset('able.s.03'), 's'), (Synset('able.s.04'), 's')] |
| >>> sent = 'people should be able to marry a person of their choice'.split() |
| >>> lesk(sent, 'able') |
| Synset('able.s.04') |
| >>> lesk(sent, 'able', pos='a') |
| Synset('able.a.01') |
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| Test behavior if there is are no matching senses. |
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|
| >>> lesk('John loves Mary'.split(), 'loves', synsets=[]) |
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