Book Image

Hands-On Deep Learning with R

By : Michael Pawlus, Rodger Devine
Book Image

Hands-On Deep Learning with R

By: Michael Pawlus, Rodger Devine

Overview of this book

Deep learning enables efficient and accurate learning from a massive amount of data. This book will help you overcome a number of challenges using various deep learning algorithms and architectures with R programming. This book starts with a brief overview of machine learning and deep learning and how to build your first neural network. You’ll understand the architecture of various deep learning algorithms and their applicable fields, learn how to build deep learning models, optimize hyperparameters, and evaluate model performance. Various deep learning applications in image processing, natural language processing (NLP), recommendation systems, and predictive analytics will also be covered. Later chapters will show you how to tackle recognition problems such as image recognition and signal detection, programmatically summarize documents, conduct topic modeling, and forecast stock market prices. Toward the end of the book, you will learn the common applications of GANs and how to build a face generation model using them. Finally, you’ll get to grips with using reinforcement learning and deep reinforcement learning to solve various real-world problems. By the end of this deep learning book, you will be able to build and deploy your own deep learning applications using appropriate frameworks and algorithms.
Table of Contents (16 chapters)
1
Section 1: Deep Learning Basics
5
Section 2: Deep Learning Applications
12
Section 3: Reinforcement Learning

Speeding up sampling with contrastive divergence

Before proceeding, we need to change up the dataset being used. While the 20 Newsgroups dataset has worked well up until this point for all the concepts on text analysis, it becomes less usable as we try to really tune our model to predict latent features. All the additional changes that we will do next actually have minimal impact on the model when using the 20 Newsgroups, so we will switch to the spam versus ham dataset, which is similar. However, instead of involving emails to a newsgroup, these are SMS text messages. In addition, instead of the target variable being a given newsgroup, the target is either that the message is spam or a legitimate text message. 

Contrastive divergence is the argument that allows us to leverage what we learned about Gibbs sampling. The value that we pass to this argument in the model will...