Deep Learning with Keras and TesorFlow

Part 3- Custom Training Loop, Hyperparameter Tunning, Model Optimization

Deep Learning with Keras and TesorFlow

Custom Training Loop

Custom Training Loops: These provide more control over the training process compared to the standard Keras fit method. You can tailor the training to specific needs, such as implementing complex strategies or custom loss functions. A simple example involves defining a model, optimizer, and loss function, and using a gradient tape for automatic differentiation.

Control Over Training Steps: You define how the model is trained, including how many epochs to run, how to handle batches of data, and how to update the model's weights.

Gradient Tape: You use TensorFlow's tf.GradientTape to record operations for automatic differentiation. This allows you to compute gradients and apply them to the model's trainable weights.

components of a custom training loop in Keras are:

  • Dataset: The data you will use for training the model.

  • Model: The neural network architecture that you are training.

  • Optimizer: The algorithm used to update the model's weights to minimize the loss.

  • Loss Function: A function that measures how well the model's predictions match the true labels.

For Implementation refer: GitHub


Hyperparameter Tunning

Hyperparameter tuning in machine learning is the process of optimizing the hyperparameters of a model to improve its performance.

Hyperparameters are the settings or configurations that are set before the training process begins, and they control how the model learns. Unlike model parameters, which are learned during training, hyperparameters must be defined beforehand.

  • Purpose: The goal is to find the best combination of hyperparameters that leads to the highest performance of the model on unseen data.

  • Examples of Hyperparameters:

    • Learning Rate: Determines how quickly the model updates its weights during training.

    • Batch Size: The number of training examples used in one iteration of training.

    • Number of Layers/Units: The architecture of the neural network, such as how many layers it has and how many neurons are in each layer.

  • Methods: Various techniques can be used for hyperparameter tuning, including:

    • Grid Search: Testing all possible combinations of hyperparameters.

    • Random Search: Randomly selecting combinations to test.

    • Bayesian Optimization: Using probabilistic models to find the best hyperparameters more efficiently.

  • Tools: Libraries like Keras Tuner help automate this process, making it easier to find the optimal hyperparameters for your model.

By tuning hyperparameters effectively, you can significantly enhance the performance of your machine learning model.

Hyperparameter tunning using keras tuner:GitHub


Model Optimization

Model optimization refers to the process of improving the performance and efficiency of machine learning models, particularly in deep learning. It involves various techniques aimed at enhancing the model's accuracy, reducing training time, and making better use of hardware resources.

Key aspects of model optimization include:

  • Improving Performance: Ensuring the model makes accurate predictions.

  • Enhancing Efficiency: Reducing the computational resources required for training and inference.

  • Scalability: Making sure the model can handle larger datasets or more complex tasks.

common techniques for model optimization include:

  • Weight Initialization: Setting initial weights to avoid issues like vanishing or exploding gradients.

  • Learning Rate Scheduling: Adjusting the learning rate dynamically during training to improve convergence.

  • Batch Normalization: Normalizing inputs to layers to accelerate training and improve convergence.

TensorFlow Tools and Techniques:

  • Mixed Precision Training: Utilizes both 16-bit and 32-bit floating point types to speed up training and reduce memory usage.

  • Knowledge Distillation: Involves training a smaller student model to replicate the behavior of a larger teacher model, making it suitable for resource-constrained devices.

  • Post-Training Techniques: Includes pruning, quantization, and dropout regularization to enhance model performance.