Pardoe Iain - Applied Regression Modeling

1. Chapter 3
2. Chapter 4
3. Chapter 5

1. Chapter 1
2. Chapter 2
3. Chapter 3
4. Chapter 4
5. Chapter 5

Third Edition

Iain Pardoe
Thompson Rivers University
The Pennsylvania State University

This edition first published 2021

2021 John Wiley & Sons, Inc

Edition History

Second Edition, 2012, John Wiley & Sons, Inc

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The right of Iain Pardoe to be identified as the author of this work has been asserted in accordance with law.

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Library of Congress CataloginginPublication Data

Names: Pardoe, Iain, 1970- author

Title: Applied regression modeling / Iain Pardoe, Thompson Rivers

University, The Pennsylvania State University.

Description: Third edition. | Hoboken, New Jersey : Wiley, [2020] |

includes bibliographical references and index.

Identifiers: LCCN 2020028117 (print) | LCCN 2020028118 (ebook) | ISBN

9781119615866 (cloth) | ISBN 9781119615880 (adobe pdf) | ISBN

9781119615903 (epub)

Subjects: LCSH: Regression analysis. | Statistics.

Classification: LCC QA278.2 .P363 2020 (print) | LCC QA278.2 (ebook) |

DDC 519.5/36dc23

LC record available at https://lccn.loc.gov/2020028117

LC ebook record available at https://lccn.loc.gov/2020028118

Cover Design: Wiley

Cover Image: Courtesy of Bethany Pardoe

To Bethany and Sierra

The first edition of this book was developed from class notes written for an applied regression course taken primarily by undergraduate business majors in their junior year at the University of Oregon. Since the regression methods and techniques covered in the book have broad application in many fields, not just business, the second edition widened its scope to reflect this. This third edition refines and improves the text further. Details of the major changes for the third edition are included at the end of this preface.

The book is suitable for any undergraduate or graduate statistics course in which regression analysis is the main focus. A recommended prerequisite is an introductory probability and statistics course. It is also appropriate for use in an applied regression course for MBAs and for vocational, professional, or other nondegree courses. Mathematical details have deliberately been kept to a minimum, and the book does not contain any calculus. Instead, emphasis is placed on applying regression analysis to data using statistical software, and understanding and interpreting results. Optional formulas are provided for those wishing to see these details and the book now includes an informal overview of matrices in the context of multiple linear regression.

), a table of critical values for the tdistribution, notation and formulas used throughout the book, a glossary of important terms, a short mathematics refresher, a tutorial on multiple linear regression using matrices, and brief answers to selected homework problems.

The first five chapters of the book have been used successfully in quarterlength courses at a number of institutions. An alternative approach for a quarterlength course would be to skip some of the material in Chapters 4 and 5 and substitute one or more of the case studies in Chapter 6 (www.wiley.com/go/pardoe/AppliedRegressionModeling3e), or briefly introduce some of the topics in Chapter 7 (www.wiley.com/go/pardoe/AppliedRegressionModeling3e). A semesterlength course could comfortably cover all the material in the book.

The website for the book, which can be found at www.wiley.com/go/pardoe/Applied RegressionModeling3e, contains supplementary material designed to help both the instructor teaching from this book and the student learning from it. There you'll find all the datasets used for examples and homework problems in formats suitable for most statistical software packages, as well as detailed instructions for using the major packages, including SPSS, Minitab, SAS, JMP, Data Desk, EViews, Stata, Statistica, R, and Python. There is also some information on using the Microsoft Excel spreadsheet package for some of the analyses covered in the book (dedicated statistical software is necessary to carry out all of the analyses). The website also includes information on obtaining a instructor's manual containing complete answers to all the homework problems, as well as instructional videos, practice quizzes, and further ideas for organizing class time around the material in the book.

The book contains the following stylistic conventions:

• When displaying calculated values, the general approach is to be as accurate as possible when it matters (such as in intermediate calculations for problems with many steps), but to round appropriately when convenient or when reporting final results for realworld questions. Displayed results from statistical software use the default rounding employed in R throughout.
• In the author's experience, many students find some traditional approaches to notation and terminology a barrier to learning and understanding. Thus, some traditions have been altered to improve ease of understanding. These include: using familiar Roman letters in place of unfamiliar Greek letters (e.g.,