Book Image

Scala for Machine Learning, Second Edition - Second Edition

Book Image

Scala for Machine Learning, Second Edition - Second Edition

Overview of this book

The discovery of information through data clustering and classification is becoming a key differentiator for competitive organizations. Machine learning applications are everywhere, from self-driving cars, engineering design, logistics, manufacturing, and trading strategies, to detection of genetic anomalies. The book is your one stop guide that introduces you to the functional capabilities of the Scala programming language that are critical to the creation of machine learning algorithms such as dependency injection and implicits. You start by learning data preprocessing and filtering techniques. Following this, you'll move on to unsupervised learning techniques such as clustering and dimension reduction, followed by probabilistic graphical models such as Naïve Bayes, hidden Markov models and Monte Carlo inference. Further, it covers the discriminative algorithms such as linear, logistic regression with regularization, kernelization, support vector machines, neural networks, and deep learning. You’ll move on to evolutionary computing, multibandit algorithms, and reinforcement learning. Finally, the book includes a comprehensive overview of parallel computing in Scala and Akka followed by a description of Apache Spark and its ML library. With updated codes based on the latest version of Scala and comprehensive examples, this book will ensure that you have more than just a solid fundamental knowledge in machine learning with Scala.
Table of Contents (27 chapters)
Scala for Machine Learning Second Edition
Credits
About the Author
About the Reviewers
www.PacktPub.com
Customer Feedback
Preface
Index

Linear regression


Although simplistic, linear regression should have a prominent place in your machine learning toolbox. The term regression is usually associated with the concept of fitting a model to data and minimizing the error between the expected and predicted values by computing the sum of square errors, residual sum of square errors, or least square errors.

Least square problems fall into two broad categories:

  • Ordinary least squares

  • Non-linear least squares

Univariate linear regression

Let's start with the simplest form of linear regression, which is single variable regression, in order to introduce the terms and concepts behind linear regression. In its simplest interpretation, one variate linear regression consists of fitting a line to a set of data points {x, y}.

Note

M1: This is a single variable linear regression for a model f, with weights wj for features xj, and labels (or expected values) yj:

Here, w1 is the slope, w0 is the intercept, f is the linear function that minimizes the...