Book Image

R Statistics Cookbook

By : Francisco Juretig
2 (2)
Book Image

R Statistics Cookbook

2 (2)
By: Francisco Juretig

Overview of this book

R is a popular programming language for developing statistical software. This book will be a useful guide to solving common and not-so-common challenges in statistics. With this book, you'll be equipped to confidently perform essential statistical procedures across your organization with the help of cutting-edge statistical tools. You'll start by implementing data modeling, data analysis, and machine learning to solve real-world problems. You'll then understand how to work with nonparametric methods, mixed effects models, and hidden Markov models. This book contains recipes that will guide you in performing univariate and multivariate hypothesis tests, several regression techniques, and using robust techniques to minimize the impact of outliers in data.You'll also learn how to use the caret package for performing machine learning in R. Furthermore, this book will help you understand how to interpret charts and plots to get insights for better decision making. By the end of this book, you will be able to apply your skills to statistical computations using R 3.5. You will also become well-versed with a wide array of statistical techniques in R that are extensively used in the data science industry.
Table of Contents (12 chapters)

Testing hypothesis

After a model is fitted, we get coefficients for each variable. In general, the relevant test is whether a coefficient is zero or not. If it is zero, it can be safely removed from the model. But sometimes we want to do more complex tests, involving possibly several variables, for example, testing whether the combined coefficients of variable1 and variable2 are equal to variable3.

The way this works is that we will define a contrast, and we will then estimate the significance for that contrast. We will do this using the multcomp package, which allows us to test linear hypotheses for lots of models.

Getting ready

In order to run this recipe, you will need to install the multcomp package via the command...