Book Image

Hands-On Data Science with R

By : Vitor Bianchi Lanzetta, Doug Ortiz, Nataraj Dasgupta, Ricardo Anjoleto Farias
Book Image

Hands-On Data Science with R

By: Vitor Bianchi Lanzetta, Doug Ortiz, Nataraj Dasgupta, Ricardo Anjoleto Farias

Overview of this book

R is the most widely used programming language, and when used in association with data science, this powerful combination will solve the complexities involved with unstructured datasets in the real world. This book covers the entire data science ecosystem for aspiring data scientists, right from zero to a level where you are confident enough to get hands-on with real-world data science problems. The book starts with an introduction to data science and introduces readers to popular R libraries for executing data science routine tasks. This book covers all the important processes in data science such as data gathering, cleaning data, and then uncovering patterns from it. You will explore algorithms such as machine learning algorithms, predictive analytical models, and finally deep learning algorithms. You will learn to run the most powerful visualization packages available in R so as to ensure that you can easily derive insights from your data. Towards the end, you will also learn how to integrate R with Spark and Hadoop and perform large-scale data analytics without much complexity.
Table of Contents (16 chapters)

Random forests – a collection of trees

It is almost a fact that combined forecasts tend to work better than single forecasts. This phenomenon is called the Wisdom of the Crowd. Random forests exploit the Wisdom of the Crowd while fitting and combining several trees. Due to this combination task, algorithms such as random forests are also called ensemble learning. Random forests are not the only ensemble learning algorithms; bagging, boosting, and committees also fit several models.

In this section, we are not only aiming at random forests but all those other kinds of models and packages that could possibly compete with them. This time we are not benchmarking accuracy only. Time elapsed will be taken into consideration. Note that it is a very simple measure and may widely vary from my end to yours.

The time needed to train a single neural network model is sometimes greater...