Book Image

Learning Predictive Analytics with R

By : Eric Mayor
Book Image

Learning Predictive Analytics with R

By: Eric Mayor

Overview of this book

This book is packed with easy-to-follow guidelines that explain the workings of the many key data mining tools of R, which are used to discover knowledge from your data. You will learn how to perform key predictive analytics tasks using R, such as train and test predictive models for classification and regression tasks, score new data sets and so on. All chapters will guide you in acquiring the skills in a practical way. Most chapters also include a theoretical introduction that will sharpen your understanding of the subject matter and invite you to go further. The book familiarizes you with the most common data mining tools of R, such as k-means, hierarchical regression, linear regression, association rules, principal component analysis, multilevel modeling, k-NN, Naïve Bayes, decision trees, and text mining. It also provides a description of visualization techniques using the basic visualization tools of R as well as lattice for visualizing patterns in data organized in groups. This book is invaluable for anyone fascinated by the data mining opportunities offered by GNU R and its packages.
Table of Contents (23 chapters)
Learning Predictive Analytics with R
Credits
About the Author
About the Reviewers
www.PacktPub.com
Preface
Exercises and Solutions
Index

Understanding Naïve Bayes


Naïve Bayes uses conditional probabilities in order to classify the observations. In this section, you will learn how it works. We will invent a simple dataset, and a disease, for this purpose. Let's have a look at the table. The table shows health behaviors of 11 individuals and whether or not 10 of them have developed DiseaseZ (the name of our made up disease) one year after these behaviors have been assessed. What we want to know is whether the individual is at risk of developing the disease. We will solve this using existing data about the individual and associations previously found in other individuals:

Smoking

Drinking

PhysicalActivity

Movies

Music

Sunbathing

DiseaseZ

YES

YES

NO

NO

NO

YES

YES

YES

NO

YES

NO

YES

YES

NO

NO

YES

NO

NO

YES

NO

YES

NO

NO

YES

NO

NO

YES

YES

YES

YES

NO

NO

NO

NO

YES

NO

NO

YES

YES

NO

NO

NO

NO

YES

...