spaCy/website/docs/api/annotation.jade

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//- 💫 DOCS > API > ANNOTATION SPECS
include ../../_includes/_mixins
p This document describes the target annotations spaCy is trained to predict.
+h(2, "tokenization") Tokenization
p
| Tokenization standards are based on the
| #[+a("https://catalog.ldc.upenn.edu/LDC2013T19") OntoNotes 5] corpus.
| The tokenizer differs from most by including tokens for significant
| whitespace. Any sequence of whitespace characters beyond a single space
| (#[code ' ']) is included as a token.
+aside-code("Example").
from spacy.en import English
nlp = English(parser=False)
tokens = nlp('Some\nspaces and\ttab characters')
print([t.orth_ for t in tokens])
# ['Some', '\n', 'spaces', ' ', 'and', '\t', 'tab', 'characters']
p
| The whitespace tokens are useful for much the same reason punctuation is
| it's often an important delimiter in the text. By preserving it in the
| token output, we are able to maintain a simple alignment between the
| tokens and the original string, and we ensure that no information is
| lost during processing.
+h(2, "sentence-boundary") Sentence boundary detection
p
| Sentence boundaries are calculated from the syntactic parse tree, so
| features such as punctuation and capitalisation play an important but
| non-decisive role in determining the sentence boundaries. Usually this
| means that the sentence boundaries will at least coincide with clause
| boundaries, even given poorly punctuated text.
+h(2, "pos-tagging") Part-of-speech Tagging
include _annotation/_pos-tags
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+h(2, "lemmatization") Lemmatization
p A "lemma" is the uninflected form of a word. In English, this means:
+list
+item #[strong Adjectives]: The form like "happy", not "happier" or "happiest"
+item #[strong Adverbs]: The form like "badly", not "worse" or "worst"
+item #[strong Nouns]: The form like "dog", not "dogs"; like "child", not "children"
+item #[strong Verbs]: The form like "write", not "writes", "writing", "wrote" or "written"
+aside("About spaCy's custom pronoun lemma")
| Unlike verbs and common nouns, there's no clear base form of a personal
| pronoun. Should the lemma of "me" be "I", or should we normalize person
| as well, giving "it" — or maybe "he"? spaCy's solution is to introduce a
| novel symbol, #[code.u-nowrap -PRON-], which is used as the lemma for
| all personal pronouns.
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p
| The lemmatization data is taken from
| #[+a("https://wordnet.princeton.edu") WordNet]. However, we also add a
| special case for pronouns: all pronouns are lemmatized to the special
| token #[code -PRON-].
+h(2, "dependency-parsing") Syntactic Dependency Parsing
include _annotation/_dep-labels
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+h(2, "named-entities") Named Entity Recognition
include _annotation/_named-entities
+h(2, "json-input") JSON input format for training
p
| spaCy takes training data in the following format:
+code("Example structure").
doc: {
id: string,
paragraphs: [{
raw: string,
sents: [int],
tokens: [{
start: int,
tag: string,
head: int,
dep: string
}],
ner: [{
start: int,
end: int,
label: string
}],
brackets: [{
start: int,
end: int,
label: string
}]
}]
}