The Art of Data Analysis: How to Answer Almost Any Question Using Basic Statistics

181 Pages·2013·6.39 MB·English

by  Kristin H. Jarman

The Art of Data Analysis

The Art of Data Analysis

How to Answer Almost Any

Question Using Basic Statistics
Kristin H. Jarman
Copyright © 2013 by John Wiley & Sons, Inc. All rights reserved
Published by John Wiley & Sons, Inc. Hoboken, New Jersey
Published simultaneously in Canada
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Ljbrary of Congress Cataloging-in-Publication Data:
Jarman, Kristin H.
The art of data analysis : how to answer almost any question using basic statistics / Kristin
H. Jarman.
pages cm
Includes bibliographical references and index.
ISBN 978-1-118-41131-5 (pbk)—ISBN 978-1-118-51492-4 (ePDF)—ISBN 978-1-118-
51494-8 (eBook)—ISBN 978-1-118-51493-1 (ePub)—ISBN 978-1-118-51490-0
(eMOBI) 1. Mathematical statistics–Popular works. I. Title.
QA276.12.J35 2013
519.5–dc23
2013000381
Printed in the United States of America
10 9 8 7 6 5 4 3 2 1
To my father: The dream lives on.

Contents
Preface ix
PART 1
The Basics
1. Statistics: The Life of the Party 3
2. Lions, and Tigers, and . . . Bigfoot? Oh, My:
How Questionable Data Can Screw Up an
Otherwise Perfectly Good Statistical Analysis 7
3. Asteroid Belts and Spandex Cars: Using
Descriptive Statistics to Answer Your Most
Weighty Questions 23
4. Baseball, Game Shows, and Sidekicks:
Who Cares about Probability Anyway? 43
5. What It’s Like to Be Normal: Probability
Distributions and One Rule That Could
Make You Wildly Popular 63
PART 2
What a Few Estimates and a Little Probability
Can Do for You
6. Men Are Insensitive and Women Are Illogical.
Really: Asserting Your Stereotypes with
Confi dence 89
vii
viii Contents
7. Godzilla versus King Kong: How Hypothesis
Tests Can Be Used to Settle the Battle of the
Movie Monsters 109
8. Lab Rats and Roommates: Analysis of
Variance and How to Channel Your Inner
Mad Scientist 129
9. When the Zombie Flu Went Viral:
Regressing the Myth Out of Urban Myths 143
Appendix A: Critical Values for the
Standard Normal Distribution 161
Appendix B: Critical Values for the
T-Distribution 163
Appendix C: Critical Values for the
Chi-Squared Distribution 165
Glossary 167
References 173
Index 175
Preface
I
remember my fi rst college statistics course. I studied hard and did
the homework. I could calculate confi dence intervals and perform
hypothesis tests. I even earned a good grade. But the subject was so
strange to me, I couldn ’ t keep the different concepts straight. Popula-
tions, estimates, p -values, these things were nothing but a jumble of
meaningless terms, and what little I learned vanished the moment I
turned in the fi nal exam.
Maybe I ’ m a masochist or maybe just determined, but I stuck with
it. I took a second statistics course and then a third. It wasn ’ t until I ’ d
earned a Ph.D. in the fi eld, worked on a number of real world problems,
and made almost every mistake imaginable that I began to feel like I
had a working grasp of statistics and its role in the data analysis process.
That ’ s where this book comes in. It ’ s driven by examples, not sta-
tistical concepts. Each chapter illustrates the application of basic sta-
tistics to a real dataset collected in the real world, far from the theorems
and formulas and neatly contrived examples of the classroom. Hope-
fully, this book will provide you with the context you need to apply the
basics of this slippery but oh-so-important subject to your own real-
world problems.
Visit http://khjarman.com/ to contact the author, read more about
the art of data analysis, and tell us your own statistical stories.
K ristin H. J arman

ix
1
PART
The Basics