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

Summary

Kernel density estimation is a classic statistical technique that is in the same family of techniques as the histogram. It allows the user to extrapolate out from sample data to make insights and predictions about the population of particular objects or events. This extrapolation comes in the form of a probability density function, which is nice because the results read as likelihoods or probabilities. The quality of this model is dependent on two parameters: the bandwidth value and the kernel function. As discussed, the most crucial component of leveraging kernel density estimation successfully is the setting of an optimal bandwidth. Optimal bandwidths are most frequently identified using grid search cross-validation with pseudo-log-likelihood as the scoring metric. What makes kernel density estimation great is both its simplicity and its applicability to so many fields.

It is routine to find kernel density estimation models in criminology, epidemiology, meteorology, and...