Book Image

Hands-On Unsupervised Learning with Python

By : Giuseppe Bonaccorso
Book Image

Hands-On Unsupervised Learning with Python

By: Giuseppe Bonaccorso

Overview of this book

Unsupervised learning is about making use of raw, untagged data and applying learning algorithms to it to help a machine predict its outcome. With this book, you will explore the concept of unsupervised learning to cluster large sets of data and analyze them repeatedly until the desired outcome is found using Python. This book starts with the key differences between supervised, unsupervised, and semi-supervised learning. You will be introduced to the best-used libraries and frameworks from the Python ecosystem and address unsupervised learning in both the machine learning and deep learning domains. You will explore various algorithms, techniques that are used to implement unsupervised learning in real-world use cases. You will learn a variety of unsupervised learning approaches, including randomized optimization, clustering, feature selection and transformation, and information theory. You will get hands-on experience with how neural networks can be employed in unsupervised scenarios. You will also explore the steps involved in building and training a GAN in order to process images. By the end of this book, you will have learned the art of unsupervised learning for different real-world challenges.
Table of Contents (12 chapters)

Dimensionality Reduction and Component Analysis

In this chapter, we will introduce and discuss some very important techniques that can be employed to perform both dimensionality reduction and component extraction. In the former case, the goal is to transform a high-dimensional dataset into a lower-dimensional one, to try to minimize the amount of information loss. The latter is a process that's needed to find a dictionary of atoms that can be mixed up, in order to build samples.

In particular, we will discuss the following topics:

  • Principal Component Analysis (PCA)
  • Singular Value Decomposition (SVD) and whitening
  • Kernel PCA
  • Sparse PCA and dictionary learning
  • Factor analysis
  • Independent Component Analysis (ICA)
  • Non-Negative Matrix Factorization (NNMF)
  • Latent Dirichlet Allocation (LDA)