Text classification is a fundamental task in natural language processing (NLP). It involves assigning a label or category to a text document based on its content. This technique is widely used in various applications, such as sentiment analysis, spam detection, and topic classification.

Overview

  • Sentiment Analysis: Determine whether a piece of text is positive, negative, or neutral.
  • Spam Detection: Identify and filter out spam messages from email or social media.
  • Topic Classification: Categorize documents into predefined topics based on their content.

Techniques

  1. Rule-Based Methods: Use predefined rules to classify text. These methods are simple but less effective for complex tasks.
  2. Machine Learning Models: Utilize machine learning algorithms, such as Naive Bayes, Support Vector Machines, and Neural Networks, to classify text.
  3. Deep Learning Models: Employ deep learning techniques, such as Convolutional Neural Networks (CNNs) and Recurrent Neural Networks (RNNs), to achieve higher accuracy.

Example

Here's a simple example of how to classify text using the Naive Bayes algorithm:

from sklearn.feature_extraction.text import CountVectorizer
from sklearn.model_selection import train_test_split
from sklearn.naive_bayes import MultinomialNB

# Sample data
data = [
    "I love this product!",
    "What a terrible experience!",
    "I don't know what to say.",
    "This is an amazing product!"
]

labels = [1, 0, -1, 1]  # 1: positive, 0: neutral, -1: negative

# Preprocess data
vectorizer = CountVectorizer()
X = vectorizer.fit_transform(data)

# Split data into training and testing sets
X_train, X_test, y_train, y_test = train_test_split(X, labels, test_size=0.2, random_state=42)

# Train the model
model = MultinomialNB()
model.fit(X_train, y_train)

# Test the model
print(model.score(X_test, y_test))

Learn More

For more information on text classification, please visit our NLP Resources.

<center><img src="https://cloud-image.ullrai.com/q/text_classification/" alt="Text Classification"/></center>