Book Image

The Unsupervised Learning Workshop

By : Aaron Jones, Christopher Kruger, Benjamin Johnston
Book Image

The Unsupervised Learning Workshop

By: Aaron Jones, Christopher Kruger, Benjamin Johnston

Overview of this book

Do you find it difficult to understand how popular companies like WhatsApp and Amazon find valuable insights from large amounts of unorganized data? The Unsupervised Learning Workshop will give you the confidence to deal with cluttered and unlabeled datasets, using unsupervised algorithms in an easy and interactive manner. The book starts by introducing the most popular clustering algorithms of unsupervised learning. You'll find out how hierarchical clustering differs from k-means, along with understanding how to apply DBSCAN to highly complex and noisy data. Moving ahead, you'll use autoencoders for efficient data encoding. As you progress, you’ll use t-SNE models to extract high-dimensional information into a lower dimension for better visualization, in addition to working with topic modeling for implementing natural language processing (NLP). In later chapters, you’ll find key relationships between customers and businesses using Market Basket Analysis, before going on to use Hotspot Analysis for estimating the population density of an area. By the end of this book, you’ll be equipped with the skills you need to apply unsupervised algorithms on cluttered datasets to find useful patterns and insights.
Table of Contents (11 chapters)
Preface

k-means versus Hierarchical Clustering

In the previous chapter, we explored the merits of k-means clustering. Now, it is important to explore where hierarchical clustering fits into the picture. As we mentioned in the Linkage section, there is some potential direct overlap when it comes to grouping data points together using centroids. Universal to all of the approaches we've mentioned so far is the use of a distance function to determine similarity. Due to our in-depth exploration in the previous chapter, we used the Euclidean distance here, but we understand that any distance function can be used to determine similarities.

In practice, here are some quick highlights for choosing one clustering method over another:

  • Hierarchical clustering benefits from not needing to pass in an explicit "k" number of clusters a priori. This means that you can find all the potential clusters and decide which clusters make the most sense after the algorithm has completed...