An Introductory Guide to R: Easing the Learning Curve

211 Pages·2022·5.004 MB·English

by  Eric L. Einspruch

AN INTRODUCTORY GUIDE TO R

An Introductory
An Introductory
Guide to
Guide to r
EEaassiinngg tthhee LLeeaarrnniinngg  CCuurrvvee
Easing
the Learning
Curve
Eric L. Einspruch
THE GUILFORD PRESS
New York London
Copyright © 2022 The Guilford Press
A Division of Guilford Publications, Inc.
370 Seventh Avenue, Suite 1200, New York, NY 10001
www.guilford.com
All rights reserved
No part of this book may be reproduced, translated, stored in a retrieval
system, or transmitted, in any form or by any means, electronic, mechanical,
photocopying, microfilming, recording, or otherwise, without written permission
from the publisher.
Printed in the United States of America
This book is printed on acid-free paper.
Last digit is print number: 9 8 7 6 5 4 3 2 1
Library of Congress Cataloging-in-Publication Data is available from the
publisher.
ISBN: 978-1-4625-4989-4 (hardcover)
ISBN: 978-1-4625-4988-7 (paperback)
Acknowledgments
I
am grateful to everyone who has in some way contributed to this
book. In particular, I very much appreciate the interest, support, and
insights of C. Deborah Laughton, Publisher, Methodology and Statistics,
and Senior Editor, Developmental Psychology and Geography, at The
Guilford Press. It has been delightful to work together again.
I want to express my gratitude to Steven R. Terrell, Nova Southeast-
ern University, and Andrew F. Hayes, University of Calgary, for granting
permission to use examples from their work. In addition, I want to thank
the reviewers who provided helpful comments on the draft manuscript:
Darlene Russ-Eft, Emeritus, College of Education, Oregon State Uni-
versity; Charlotte Tate, Department of Psychology, San Francisco State
University; Michele Parker, Department of Educational Leadership,
University of North Carolina, Wilmington; Julie Combs, Department
of Educational Leadership, Sam Houston State University; Katerina
M. Marcoulides, Psychology, University of Minnesota; and Sierra A.
Bainter, Psychology, University of Miami. I also thank the R Foundation
and RStudio for allowing use of images and output from R and RStudio.
I remain ever grateful to family members, friends, colleagues, and
students who have supported my interests and contributed to my educa-
tion across the years.
v

Contents
Introduction
CHAPTER 1. 1
Purpose of This Book 1
What You Will Be Able to Do after Reading This Book 2
Whom This Book Is For 3
Approach 3
Key Takeaways 5
Getting Started
CHAPTER 2. 6
Download and Install R 7
Download and Install RStudio 10
RStudio Fundamentals 10
Download, Install, and Load R Packages 17
Read Data into R 19
Write Data Files 26
Entering Data via Inline Code 26
Cleaning Variable Names 27
Clearing the Console 27
Clearing the Environment 28
Some Thoughts on Debugging R Code 28
Key Takeaways 30
Exercises 31
Data Wrangling
CHAPTER 3. 32
Example Data 33
The Pipe 34
Select Variables 34
Select Cases 37
vii