How to use a recurrent neural network (RNN) for text classification in Keras?

Published on Aug. 22, 2023, 12:19 p.m.

To use a recurrent neural network (RNN) for text classification in Keras, you’ll need to perform the following steps:

  1. Prepare your data: Convert your textual data into numerical representation that can be used as input to an RNN. This can involve doing preprocessing such as tokenization, cleaning up the data, normalizing the text, and encoding the input data.
  2. Build your RNN model: Use Keras to define your RNN architecture. Some popular RNN architectures for text classification include Long Short-Term Memory (LSTM), Gated Recurrent Unit (GRU), and SimpleRNN.
  3. Compile your model: Specify the training process by setting your loss function, optimizer, and evaluation metrics.
  4. Train your model: Pass your training data to the model and train it for a certain number of epochs.
  5. Evaluate your model: Use your validation data to evaluate the performance of the model and adjust it accordingly.
  6. Use your model to make predictions: Once your model is trained and evaluated, you can use it to make predictions on new text data.

Here’s an example code snippet for building an LSTM model for text classification in Keras:

from keras.models import Sequential
from keras.layers import Embedding, LSTM, Dense

model = Sequential()
model.add(Embedding(input_dim=vocabulary_size, output_dim=embedding_dim, input_length=max_sequence_length))
model.add(LSTM(units=128, dropout=0.2, recurrent_dropout=0.2))
model.add(Dense(1, activation='sigmoid'))

model.compile(optimizer='adam', loss='binary_crossentropy', metrics=['accuracy'])
model.fit(train_sequences, train_labels, validation_data=(val_sequences, val_labels), epochs=10, batch_size=128)

In this code, we are building a sequential model with an embedding layer, followed by an LSTM layer and finally, a Dense output layer with a sigmoid activation function. We’re compiling the model with the Adam optimizer and binary cross-entropy loss function for binary classification. Finally, we’re fitting the model on the training data with a batch size of 128 for 10 epochs, and evaluating it on the validation data.

Note that the actual implementation may depend on the specific details of your use case and the type of text classification problem you are trying to solve.