Interpreting and Using Statistics in Psychological Research. Andrew N. Christopher

      

Interpreting and Using Statistics in Psychological Research

      Interpreting and Using Statistics in Psychological Research

       Andrew N. Christopher

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       Library of Congress Cataloging-in-Publication Data

      Names: Christopher, Andrew N., author.

      Title: Interpreting and using statistics in psychological research / Andrew N. Christopher.

      Description: Los Angeles : SAGE Publications, [2017] | Includes bibliographical references and index.

      Identifiers: LCCN 2016013368 | ISBN 978-1-5063-0416-8 (pbk. : alk. paper)

      Subjects: LCSH: Psychology—Statistical methods. | Psychometrics. | Psychology—Research—Methodology.

      Classification: LCC BF39 .C48855 2017 | DDC 150.1/5195—dc23 LC record available at https://lccn.loc.gov/2016013368

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      Preface

      In almost any class at my college, there is a natural gap between the teacher’s enthusiasm for the subject matter and the students’ level of enthusiasm for that same material. This makes sense. The teacher has made a career of that subject matter, whereas students are still learning to appreciate it. Perhaps in no class within psychology is this enthusiasm gap wider than it is in statistics classes. This is unfortunate, as statistics are useful not only for interpreting and conducting research but also in navigating many of life’s everyday situations. I make no qualms about my love for statistics. They can be, once understood, powerful tools not only in research but also in many life situations more generally. Most of my students come into this class with dread and apprehension about what’s to come. Most of these same students leave the class with reactions such as “It wasn’t that bad,” and some even admit “It was pretty interesting.” Indeed, I want all students to see statistics as at least “pretty interesting,” and I am hoping this book can help you not only learn statistics but also see the practical value they hold.

      Guiding philosophy of this book

      Teachers in the social sciences are fortunate to have inherently interesting material to discuss with students. However, the research process used to systematically investigate our subject matter is of lesser interest to many students. I can understand why. To paraphrase from a conversation with a colleague at another college, when learning about various statistics, students get lost in a myriad of symbols, numbers, and formulas, and when they finish calculating a statistic, they often have no idea what it means or how to use it. Indeed, to many students, statistics courses tend to be an evil necessity. Therefore, this book attempts to use the inherently interesting content of the discipline as the basis for teaching the statistical techniques we use to learn about the subject matter. In a sense, this book starts its discussions of statistical tools with what people often find interesting and then discusses the statistical tools needed to discern such information.

      This book is written in the same tone as I teach in the classroom. I mention this because there are attempts at humor throughout (notice I said “attempts at humor”). Indeed, statistical information does not come naturally to many of us (yes, that does include me, as you’ll see in Chapter 1). Anything to add some lightheartedness to a potentially intimidating subject matter, I firmly believe, can only hold your attention. I know when I read books as an undergraduate student, I never appreciated that there was a person on the other end trying to teach me. I hope you will be able to have that appreciation reading this book.

      Most psychology and social science majors will not go into research-specific careers. You may or may not pursue this career path. Regardless of your eventual career route, this book allows you to become skilled at using and interpreting statistical information with which you are presented. Being able to competently interpret statistical information is a skill needed in almost any career and is essential to being a liberally educated citizen. For those who do go into research-related careers, this book will show you how to conduct and interpret statistical analyses as they are conducted when one engages in research. If you are thinking about a research-oriented career, you will want to gain research experience outside the classroom. Indeed, after reading this book, you will be able to make valuable contributions to a faculty member’s research lab with respect to both conceptual understanding of tools and the ability to conduct and interpret the statistical tools presented in this book.

      Content organization

      Chapter 1 begins with an overview of why learning about statistics is important, not so much in research, but in life more generally. As human beings, we are remarkably efficient at navigating the world around us. However, such