Book Image

Applied Supervised Learning with R

By : Karthik Ramasubramanian, Jojo Moolayil
Book Image

Applied Supervised Learning with R

By: Karthik Ramasubramanian, Jojo Moolayil

Overview of this book

R provides excellent visualization features that are essential for exploring data before using it in automated learning. Applied Supervised Learning with R helps you cover the complete process of employing R to develop applications using supervised machine learning algorithms for your business needs. The book starts by helping you develop your analytical thinking to create a problem statement using business inputs and domain research. You will then learn different evaluation metrics that compare various algorithms, and later progress to using these metrics to select the best algorithm for your problem. After finalizing the algorithm you want to use, you will study the hyperparameter optimization technique to fine-tune your set of optimal parameters. The book demonstrates how you can add different regularization terms to avoid overfitting your model. By the end of this book, you will have gained the advanced skills you need for modeling a supervised machine learning algorithm that precisely fulfills your business needs.
Table of Contents (12 chapters)
Applied Supervised Learning with R
Preface

XGBoost


XGBoost is the most popular boosting technique in recent times. Although there have been various new versions that have been developed by large corporations, XGBoost still remains the undisputed king. Let's look at a brief history of boosting.

How Does the Boosting Process Work?

Boosting differs from bagging in its core principles; the learning process is, in fact, sequential. Every model built in an ensemble is ideally an improved version of the previous model. To understand boosting in simple terms, imagine you are playing a game where you must remember all the objects placed on the table that you are shown just once for 30 seconds. The moderator of the game arranges around 50-100 different objects on a table, such as a bat, ball, clock, die, coins, and so on, and covers them with a large piece of cloth. When the game begins, he withdraws the cloth from the table and gives you exactly 30 seconds to see them and puts the curtain back. You now must recollect all the objects you can...