Book Image

Neural Networks with R

By : Balaji Venkateswaran, Giuseppe Ciaburro
Book Image

Neural Networks with R

By: Balaji Venkateswaran, Giuseppe Ciaburro

Overview of this book

Neural networks are one of the most fascinating machine learning models for solving complex computational problems efficiently. Neural networks are used to solve wide range of problems in different areas of AI and machine learning. This book explains the niche aspects of neural networking and provides you with foundation to get started with advanced topics. The book begins with neural network design using the neural net package, then you’ll build a solid foundation knowledge of how a neural network learns from data, and the principles behind it. This book covers various types of neural network including recurrent neural networks and convoluted neural networks. You will not only learn how to train neural networks, but will also explore generalization of these networks. Later we will delve into combining different neural network models and work with the real-world use cases. By the end of this book, you will learn to implement neural network models in your applications with the help of practical examples in the book.
Table of Contents (14 chapters)
Title Page
Credits
About the Authors
About the Reviewer
www.PacktPub.com
Customer Feedback
Preface

Unsupervised learning in neural networks 


In this section, we present unsupervised learning models in neural network, named competitive learning and Kohonen SOM. Kohonen SOM was invented by a professor named Teuvo Kohonen and is a way to represent multidimensional data in much lower dimensions: 1D or 2D. It can classify data without supervision. Unsupervised learning aims at finding hidden patterns within the dataset and clustering them into different classes of data.

There are many unsupervised learning techniques, namely K-means clustering, dimensionality reduction, EM, and so on. The common feature is that there is no input-output mapping and we work only on the input values to create a group or set of outputs. 

For the case of neural networks, they can be used for unsupervised learning. They can group data into different buckets (clustering) or abstract original data into a different set of output data points (feature abstraction or dimensionality reduction). Unsupervised techniques require...