Book Image

Machine Learning with Swift

By : Jojo Moolayil, Alexander Sosnovshchenko, Oleksandr Baiev
Book Image

Machine Learning with Swift

By: Jojo Moolayil, Alexander Sosnovshchenko, Oleksandr Baiev

Overview of this book

Machine learning as a field promises to bring increased intelligence to the software by helping us learn and analyse information efficiently and discover certain patterns that humans cannot. This book will be your guide as you embark on an exciting journey in machine learning using the popular Swift language. We’ll start with machine learning basics in the first part of the book to develop a lasting intuition about fundamental machine learning concepts. We explore various supervised and unsupervised statistical learning techniques and how to implement them in Swift, while the third section walks you through deep learning techniques with the help of typical real-world cases. In the last section, we will dive into some hard core topics such as model compression, GPU acceleration and provide some recommendations to avoid common mistakes during machine learning application development. By the end of the book, you'll be able to develop intelligent applications written in Swift that can learn for themselves.
Table of Contents (18 chapters)
Title Page
Packt Upsell
Contributors
Preface
Index

Fixing linear regression problems with regularization


As we've seen, one outlier is enough to break the least-squares regression. Such instability is a manifestation of overfitting problems. Methods that help prevent models from overfitting are generally referred to as regularization techniques. Usually, regularization is achieved by imposing additional constraints on the model. This can be an additional term in a loss function, noise injection, or something else. We've already implemented one such technique previously, in Chapter 3, K-Nearest Neighbors Classifier. Locality constraint w in the DTW algorithm is essentially a way to regularize the result. In the case of linear regression, regularization imposes constraints on the weights vector values.

Ridge regression and Tikhonov regularization

Under the standard least squares method, the obtained regression coefficients can vary wildly. We can formulate the least squares regression as an optimization problem:

What we have on the right here...