# 🈴🈯️ Token Classification#

Token classification kind-of-tasks are NLP tasks aimed to divide the input text into words, or syllables, and assign certain values to them. Think about giving each word in a sentence its grammatical category, or highlight which parts of a medical report belong to a certain speciality. There are some popular ones like NER or POS-tagging. For this part of the article, we will use spaCy with Argilla to track and monitor Token Classification tasks.

Remember to install spaCy and datasets, or running the following cell.

[ ]:

%pip install datasets -qqq
%pip install -U spacy -qqq
%pip install protobuf


## NER#

Named entity recognition (NER) is the task of tagging entities in text with their corresponding type. Approaches typically use BIO notation, which differentiates the beginning (B) and the inside (I) of entities. O is used for non-entity tokens.

For this tutorial, we’re going to use the Gutenberg Time dataset from the Hugging Face Hub. It contains all explicit time references in a dataset of 52,183 novels whose full text is available via Project Gutenberg. From extracts of novels, we are surely going to find some NER entities. We will also use the en_core_web_trf pretrained English model, a Roberta-based spaCy model. If you do not have them installed, run:

[ ]:

!python -m spacy download en_core_web_trf #Download the model

[ ]:

import argilla as rg
import spacy

records = []

for record in dataset:
# We only need the text of each instance
text = record["tok_context"]

# spaCy Doc creation
doc = nlp(text)

# Prediction entities with the tuples (label, start character, end character)
entities = [(ent.label_, ent.start_char, ent.end_char) for ent in doc.ents]

# Pre-tokenized input text
tokens = [token.text for token in doc]

# Argilla TokenClassificationRecord list
records.append(
rg.TokenClassificationRecord(
text=text,
tokens=tokens,
prediction=entities,
prediction_agent="en_core_web_trf",
)
)

# Logging into Argilla
rg.log(
records=records,
name="ner",
tags={
"family": "token-classification",
"dataset": "gutenberg-time",
},
)


## POS tagging#

A POS tag (or part-of-speech tag) is a special label assigned to each word in a text corpus to indicate the part of speech and often also other grammatical categories such as tense, number, case etc. POS tags are used in corpus searches and in-text analysis tools and algorithms.

We will be repeating duo for this second spaCy example, with the Gutenberg Time dataset from the Hugging Face Hub and the en_core_web_trf pretrained English model.

[ ]:

import argilla as rg
import spacy

records = []

for record in dataset:
# We only need the text of each instance
text = record["tok_context"]

# spaCy Doc creation
doc = nlp(text)

# Creating the prediction entity as a list of tuples (tag, start_char, end_char)
prediction = [(token.pos_, token.idx, token.idx + len(token)) for token in doc]

# Argilla TokenClassificationRecord list
records.append(
rg.TokenClassificationRecord(
text=text,
tokens=[token.text for token in doc],
prediction=prediction,
prediction_agent="en_core_web_trf",
)
)

# Logging into Argilla
rg.log(
records=records,
name="pos-tagging",
tags={