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Text Classification

Text Classification

Learn about text classification and how to do it using Python.

We'll cover the following...

Introduction

When we build machine-learning models, we use the text classification technique as a first step to overcome the lack of labels, especially when we have two datasets: one dataset with labels and the other without.

In the context of text classification, a label is a categorical variable that we want to predict.

This process involves creating a new label for the second dataset using an existing text classification model. Therefore, we define text classification as a technique that classifies text content into predefined groups or categories. Here’s a table of a few commonly used classifiers for text classification and a brief description of when to use each:

Text Classification Classifiers

Classifier Name

When We Use It

Python Implementation Class

Naive Bayes

When we have a small text dataset and want a simple baseline

sklearn.naive_bayes.MultinomialNB

Logistic regression

When we need a fast and interpretable classifier

sklearn.linear_model.LogisticRegression

Support vector machines

When we have a high-dimensional text dataset

sklearn.svm.SVC

Random forest

When we have a dataset with lots of outliers and noisy data

sklearn.ensemble.RandomForestClassifier

Gradient boosting

When we need high accuracy and can handle longer training times

sklearn.ensemble.GradientBoostingClassifier

Application

The following code example showcases creating a new label for an unlabeled dataset ...