Book Image

R Deep Learning Essentials - Second Edition

By : Mark Hodnett, Joshua F. Wiley
Book Image

R Deep Learning Essentials - Second Edition

By: Mark Hodnett, Joshua F. Wiley

Overview of this book

Deep learning is a powerful subset of machine learning that is very successful in domains such as computer vision and natural language processing (NLP). This second edition of R Deep Learning Essentials will open the gates for you to enter the world of neural networks by building powerful deep learning models using the R ecosystem. This book will introduce you to the basic principles of deep learning and teach you to build a neural network model from scratch. As you make your way through the book, you will explore deep learning libraries, such as Keras, MXNet, and TensorFlow, and create interesting deep learning models for a variety of tasks and problems, including structured data, computer vision, text data, anomaly detection, and recommendation systems. You’ll cover advanced topics, such as generative adversarial networks (GANs), transfer learning, and large-scale deep learning in the cloud. In the concluding chapters, you will learn about the theoretical concepts of deep learning projects, such as model optimization, overfitting, and data augmentation, together with other advanced topics. By the end of this book, you will be fully prepared and able to implement deep learning concepts in your research work or projects.
Table of Contents (13 chapters)

Use case – improving out-of-sample model performance using dropout

Dropout is a novel approach to regularization that is particularly valuable for large and complex deep neural networks. For a much more detailed exploration of dropout in deep neural networks, see Srivastava, N., Hinton, G., Krizhevsky, A., Sutskever, I., and Salakhutdinav, R. (2014). The concept behind dropout is actually quite straightforward. During the training of the model, units (for example, input and hidden neurons) are probabilistically dropped along with all connections to and from them.

For example, the following diagram is an example of what might happen at each step of training for a model where hidden neurons and their connections are dropped with a probability of 1/3 for each epoch. Once a node is dropped, its connections to the next layer are also dropped. In the the following diagram, the...