ix

Statistics as a Liberal Discipline

Statistics: Concepts and Controversies (SCC) is a book on statistics as a liberal discipline—that is, as part of the general education of “nonmathematical” students. The book grew out of one of the author’s experience in developing and teaching a course for freshmen and sophomores from Purdue University’s School of Liberal Arts. We are pleased that other teachers have found SCC useful for unusually diverse audiences, extending as far as students of philosophy and medicine. This ninth edition is a revision of the text with several new features. It retains, however, the goals of the original: to present statistics not as a technical tool but as part of the intellectual culture that educated people share.

Statistics among the liberal arts

Statistics has a widespread reputation as the least liberal of subjects. When statistics is praised, it is most often for its usefulness. Health professionals need statistics to read accounts of medical research; managers need statistics because efficient crunching of numbers will find its way to the bottom line; citizens need statistics to understand opinion polls and government statistics such as the unemployment rate and the Consumer Price Index. Because data and chance are omnipresent, our propaganda line goes like this: everyone will find statistics useful, and perhaps even profitable.

This is true. We would even argue that for most students, the conceptual and verbal approach in SCC is better preparation for future encounters with statistical studies than the usual methods-oriented introduction. The joint curriculum committee of the American Statistical Association and the Mathematical Association of America recommends that any first course in statistics “emphasize the elements of statistical thinking” and feature “more data and concepts, fewer recipes and derivations.” SCC does this, with the flavor appropriate to a liberal education: more concepts, more thinking, only simple data, fewer recipes, and no formal derivations.

There is, however, another justification for learning about statistical ideas: statistics belongs among the liberal arts. A liberal education emphasizes fundamental intellectual skills—that is, general methods of inquiry that apply in a wide variety of settings. The traditional liberal arts present such methods: literary and historical studies, the political and social analysis of human societies, the probing of nature by experimental science, the power of abstraction and deduction in mathematics. The case that statistics belongs among the liberal arts rests on the fact that reasoning from uncertain empirical data is a similarly general intellectual method. Data and chance, the topics of this book, are pervasive aspects of our experience. Though we employ the tools of mathematics to work with data and chance, the mathematics implements ideas that are not strictly mathematical. In fact, psychologists argue convincingly that mastering formal mathematics does little to improve our ability to reason effectively about data and chance in everyday life.

x

SCC is shaped, as far as the limitations of the authors and the intended readers allow, by the view that statistics is an independent and fundamental intellectual method. The focus is on statistical thinking, on what others might call quantitative literacy or numeracy.

The nature of this book

There are books on statistical theory and books on statistical methods. This is neither. It is a book on statistical ideas and statistical reasoning and on their relevance to public policy and to the human sciences from medicine to sociology. We have included many elementary graphical and numerical techniques to give flesh to the ideas and muscle to the reasoning. Students learn to think about data by working with data. We have not, however, allowed technique to dominate concepts. Our intention is to teach verbally rather than algebraically, to invite discussion and even argument rather than mere computation, though some computation remains essential. The coverage is considerably broader than one might traditionally cover in a one-term course, as the table of contents reveals. In the spirit of general education, we have preferred breadth to detail.

Despite its informal nature, SCC is a textbook. It is organized for systematic study and has abundant exercises, many of which ask students to offer a discussion or make a judgment. Even those admirable individuals who seek pleasure in uncompelled reading should look at the exercises as well as the text. Teachers should be aware that the book is more serious than its low mathematical level suggests. The emphasis on ideas and reasoning asks more of the reader than many recipe-laden methods texts.

New in this edition

We welcome three new contributors to this edition of SCC. Professors Jackie Miller (University of Michigan), Leslie Hendrix (University of South Carolina), and Michelle Everson (The Ohio State University) assisted with Chapters 3, 4, 8, 9, 10, 11, 13, 21, 22, 23, and 24. They bring a fresh perspective to SCC while being sensitive to the fundamental nature of the book.

xi

This new version of a classic text fits the current teaching environment while continuing to present statistics to “nonmathematical” readers as an aid to clear thinking in personal and professional life. The following new features and enhancements build on SCC ’s strong pedagogical foundation:

In addition to the new ninth edition enhancements, SCC has retained the successful pedagogical features from previous editions:

xiii

Media and Supplements

LaunchPad, our online course space, combines an interactive e-Book with high-quality multimedia content and ready-made assessment options, including LearningCurve adaptive quizzing and coded machine-gradable exercises from the textbook. Content is easy to assign or adapt with your own material, such as readings, videos, quizzes, discussion groups, and more. LaunchPad also provides access to a Gradebook that offers a window into your students’ performance—either individually or as a whole. Use LaunchPad on its own or integrate it with your school’s learning management system so your class is always on the same page. To learn more about LaunchPad for Statistics: Concepts and Controversies, Ninth Edition, or to request access, go to launchpadworks.com.

Assets integrated into LaunchPad include:

Interactive e-Book. Every LaunchPad e-Book comes with powerful study tools for students, video and multimedia content, and easy customization for instructors. Students can search, highlight, and bookmark, making it easier to study and access key content. And teachers can ensure that their classes get just the book they want to deliver: they can customize and rearrange chapters; add-share notes and discussions; and link to quizzes, activities, and other resources.

xiv

LearningCurve provides students and instructors with powerful adaptive quizzing, a game-like format, direct links to the e-Book, and instant feedback. The quizzing system features questions tailored specifically to the text and adapts to students’ responses, providing material at different difficulty levels and topics based on student performance.

JMP Student Edition (developed by SAS) is easy to learn and contains all the capabilities required for introductory statistics. JMP is the leading commercial data analysis software of choice for scientists, engineers, and analysts at companies throughout the world (for Windows and Mac). Register inside LaunchPad at no additional cost.

CrunchIt!® is a Web-based statistical program that allows users to perform all the statistical operations and graphing needed for an introductory statistics course and more. It saves users time by automatically loading data from Statistics: Concepts and Controversies, Ninth Edition, and it provides the flexibility to edit and import additional data.

StatBoards Videos are brief whiteboard videos that illustrate difficult topics through additional examples, written and explained by a select group of statistics educators.

Stepped Tutorials are centered on algorithmically-generated quizzing with step-by-step feedback to help students work their way toward the correct solution. These exercise tutorials (two to three per chapter) are easily assignable and assessable.

Statistical Video Series consists of StatClips, StatClips Examples, and Statistically Speaking “Snapshots.” View animated lecture videos, whiteboard lessons, and documentary-style footage that illustrate key statistical concepts and help students visualize statistics in real-world scenarios.

Video Technology Manuals, available for TI-83/84 calculators, Minitab, Excel, JMP, SPSS, R, Rcmdr, and CrunchIt!®, provide brief instructions for using specific statistical software.

StatTutor Tutorials offer multimedia tutorials that explore important concepts and procedures in a presentation that combines video, audio, and interactive features. The newly revised format includes built-in, assignable assessments and a bright new interface.

xv

Statistical Applets give students hands-on opportunities to familiarize themselves with important statistical concepts and procedures, in an interactive setting that allows them to manipulate variables and see the results graphically. Icons in the textbook indicate when an applet is available for the material being covered. Applets are assessable and assignable in LaunchPad.

Stats@Work Simulations put students in the role of the statistical consultant, helping them better understand statistics interactively within the context of real-life scenarios.

EESEE Case Studies (Electronic Encyclopedia of Statistical Examples and Exercises), developed by The Ohio State University Statistics Department, teach students to apply their statistical skills by exploring actual case studies using real data.

SolutionMaster offers an easy-to-use web-based version of the instructor’s solutions, allowing instructors to generate a solution file for any set of homework exercises.

Data files are available in JMP, ASCII, Excel, TI, Minitab, SPSS (an IBM Company)^*, R, and CSV formats.

Lab and Activities Manual by Dennis Pearl, The Ohio State University. This manual provides a variety of projects and exercises to help students develop a fuller appreciation of statistical concepts. It features computer lab and hands-on activities illustrating key concepts in the text as well as additional end-of-chapter-type problems and activities. Additionally, there are exercises based on the statistical applets and EESEE Case Studies (both accessed through LaunchPad).

Instructor’s Guide with Solutions includes teaching suggestions, chapter comments, and detailed solutions to all exercises and is available electronically in LaunchPad.

Test Bank offers hundreds of multiple-choice questions and is available in LaunchPad.

Lecture Slides offer a customizable, detailed lecture presentation of statistical concepts covered in each chapter of SCC. Image Slides contain all textbook figure and tables. Lecture slides and images slides are available in LaunchPad.

xvi

Additional Resources Available with Statistics: Concepts and Controversies, Ninth Edition

Special Software Package A student version of JMP is available for packaging with the printed text. JMP is also available inside LaunchPad at no additional cost.

i-clicker is a two-way radio-frequency classroom response solution developed by educators for educators. Each step of i-clicker’s development has been informed by teaching and learning.

Acknowledgments

A very special thank you to Jackie Miller, University of Michigan; Leslie Hendrix, University of South Carolina; and Michelle Everson, The Ohio State University for their invaluable contributions to this edition. Thanks also to Michelle Everson for carefully accuracy checking the book.

Thank you to the instructors who authored and accuracy reviewed supplements for the book: Michelle Duda at Columbus State Community College for authoring solutions and Karen Starin at Columbus State Community College for accuracy reviewing the solutions; Mark A. Gebert at University of Kentucky–Lexington for authoring the test bank and Soma Roy at California Polytechnic State University–San Luis Obispo for accuracy reviewing the test bank; and Leslie Hendrix for authoring the lecture slides and i-clicker slides.

The staff of W. H. Freeman, especially Karen Carson, Jorge Amaral, Catriona Kaplan, Victoria Garvey, Blake Logan, and Susan Wein, have done their usual excellent job in editing, designing, and producing the book. Special thanks also to Edward Dionne.

We are grateful to the many colleagues who commented on successive drafts of the manuscript for this edition (listed below). We are also grateful to those who reviewed previous editions (a full list is available at www.macmillanlearning.com/scc9e).