Book Image

Hands-On Ensemble Learning with R

By : Prabhanjan Narayanachar Tattar
Book Image

Hands-On Ensemble Learning with R

By: Prabhanjan Narayanachar Tattar

Overview of this book

Ensemble techniques are used for combining two or more similar or dissimilar machine learning algorithms to create a stronger model. Such a model delivers superior prediction power and can give your datasets a boost in accuracy. Hands-On Ensemble Learning with R begins with the important statistical resampling methods. You will then walk through the central trilogy of ensemble techniques – bagging, random forest, and boosting – then you'll learn how they can be used to provide greater accuracy on large datasets using popular R packages. You will learn how to combine model predictions using different machine learning algorithms to build ensemble models. In addition to this, you will explore how to improve the performance of your ensemble models. By the end of this book, you will have learned how machine learning algorithms can be combined to reduce common problems and build simple efficient ensemble models with the help of real-world examples.
Table of Contents (17 chapters)
Hands-On Ensemble Learning with R
Contributors
Preface
12
What's Next?
Index

Chapter 9. Ensembling Regression Models

Chapters 3, Bagging, to Chapters 8, Ensemble Diagnostics, were devoted to learning different types of ensembling methods. The discussion was largely based on the classification problem. If the regressand/output of the supervised learning problem is a numeric variable, then we have a regression problem, which will be addressed here. The housing price problem is selected for demonstration purposes throughout the chapter, and the dataset is chosen from a Kaggle competition: https://www.kaggle.com/c/house-prices-advanced-regression-techniques/. The data consists of numerous variables, including as many as 79 independent variables, with the price of the house as the output/dependent variable. The dataset needs some pre-processing as some variables have missing dates, some variables have lots of levels, with a few of them only occurring very rarely, and some variables have missing data in more than 20% of observations.

The pre-processing techniques will...