Book Image

Supervised Machine Learning with Python

By : Taylor Smith
Book Image

Supervised Machine Learning with Python

By: Taylor Smith

Overview of this book

Supervised machine learning is used in a wide range of sectors, such as finance, online advertising, and analytics, to train systems to make pricing predictions, campaign adjustments, customer recommendations, and much more by learning from the data that is used to train it and making decisions on its own. This makes it crucial to know how a machine 'learns' under the hood. This book will guide you through the implementation and nuances of many popular supervised machine learning algorithms, and help you understand how they work. You’ll embark on this journey with a quick overview of supervised learning and see how it differs from unsupervised learning. You’ll then explore parametric models, such as linear and logistic regression, non-parametric methods, such as decision trees, and a variety of clustering techniques that facilitate decision-making and predictions. As you advance, you'll work hands-on with recommender systems, which are widely used by online companies to increase user interaction and enrich shopping potential. Finally, you’ll wrap up with a brief foray into neural networks and transfer learning. By the end of this book, you’ll be equipped with hands-on techniques and will have gained the practical know-how you need to quickly and effectively apply algorithms to solve new problems.
Table of Contents (11 chapters)
Title Page
Copyright and Credits
About Packt

Parametric models

When it comes to supervised learning, there are two families of learning algorithms: parametric and non-parametric. This area also happens to be a hotbed for gatekeeping and opinion-based conjecture regarding which is better. Basically, parametric models are finite-dimensional, which means that they can learn only a defined number of model parameters. Their learning stage is typically categorized by learning some vector theta, which is also called a coefficient. Finally, the learning function is often a known form, which we will clarify later in this section.

Finite-dimensional models

If we go back to our definition of supervised learning, recall that we need to learn some function, f. A parametric model will summarize the mapping between X, our matrix, and y, our target, within a constrained number of summary points. The number of points is typically related to the number of features in the input data. So, if there are three variables, f will try to summarize the relationship...