Welcome to *Introductory Statistics 2e*, an OpenStax resource. This textbook was written to increase student access to high-quality learning materials, maintaining highest standards of academic rigor at little to no cost.

The foundation of this textbook is *Collaborative Statistics*, by Barbara Illowsky and Susan Dean. Additional topics, examples, and innovations in terminology and practical applications have been added, all with a goal of increasing relevance and accessibility for students.

## About OpenStax

OpenStax is a nonprofit based at Rice University, and it’s our mission to improve student access to education. Our first openly licensed college textbook was published in 2012, and our library has since scaled to over 25 books for college and AP^{®} courses used by hundreds of thousands of students. OpenStax Tutor, our low-cost personalized learning tool, is being used in college courses throughout the country. Through our partnerships with philanthropic foundations and our alliance with other educational resource organizations, OpenStax is breaking down the most common barriers to learning and empowering students and instructors to succeed.

## About OpenStax's resources

### Customization

*Introductory Statistics 2e* is licensed under a Creative Commons Attribution 4.0 International (CC BY) license, which means that you can distribute, remix, and build upon the content, as long as you provide attribution to OpenStax and its content contributors.

Because our books are openly licensed, you are free to use the entire book or pick and choose the sections that are most relevant to the needs of your course. Feel free to remix the content by assigning your students certain chapters and sections in your syllabus, in the order that you prefer. You can even provide a direct link in your syllabus to the sections in the web view of your book.

Instructors also have the option of creating a customized version of their OpenStax book. The custom version can be made available to students in low-cost print or digital form through their campus bookstore. Visit your book page on OpenStax.org for more information.

### Art Attribution

In *Introductory Statistics 2e*, most art contains attribution to its title, creator or rights holder, host platform, and license within the caption. Because the art is openly licensed, anyone may reuse the art as long as they provide the same attribution to its original source.

To maximize readability and content flow, some art does not include attribution in the text. If you reuse illustrations, graphs, or charts from this text that do not have attribution provided, use the following attribution: Copyright Rice University, OpenStax, under CC BY 4.0 license.

### Errata

All OpenStax textbooks undergo a rigorous review process. However, like any professional-grade textbook, errors sometimes occur. Since our books are web based, we can make updates periodically when deemed pedagogically necessary. If you have a correction to suggest, submit it through the link on your book page on OpenStax.org. Subject matter experts review all errata suggestions. OpenStax is committed to remaining transparent about all updates, so you will also find a list of past errata changes on your book page on OpenStax.org.

### Format

You can access this textbook for free in web view or PDF through OpenStax.org, and in low-cost print and iBooks editions.

## About *Introductory Statistics 2e*

*Introductory Statistics 2e* follows scope and sequence requirements of a one-semester introduction to statistics course and is geared toward students majoring in fields other than math or engineering. The text assumes some knowledge of intermediate algebra and focuses on statistics application over theory. *Introductory Statistics 2e* includes innovative practical applications that make the text relevant and accessible, as well as collaborative exercises, technology integration problems, and statistics labs.

### Coverage and scope

Chapter 1 Sampling and Data

Chapter 2 Descriptive Statistics

Chapter 3 Probability Topics

Chapter 4 Discrete Random Variables

Chapter 5 Continuous Random Variables

Chapter 6 The Normal Distribution

Chapter 7 The Central Limit Theorem

Chapter 8 Confidence Intervals

Chapter 9 Hypothesis Testing with One Sample

Chapter 10 Hypothesis Testing with Two Samples

Chapter 11 The Chi-Square Distribution

Chapter 12 Linear Regression and Correlation

Chapter 13 F Distribution and One-Way ANOVA

### Alternate sequencing

*Introductory Statistics 2e* was conceived and written to fit a particular topical sequence, but it can be used flexibly to accommodate other course structures. One such potential structure, which fits reasonably well with the textbook content, is provided below. Please consider, however, that the chapters were not written to be completely independent, and that the proposed alternate sequence should be carefully considered for student preparation and textual consistency.

Chapter 1 Sampling and Data

Chapter 2 Descriptive Statistics

Chapter 12 Linear Regression and Correlation

Chapter 3 Probability Topics

Chapter 4 Discrete Random Variables

Chapter 5 Continuous Random Variables

Chapter 6 The Normal Distribution

Chapter 7 The Central Limit Theorem

Chapter 8 Confidence Intervals

Chapter 9 Hypothesis Testing with One Sample

Chapter 10 Hypothesis Testing with Two Samples

Chapter 11 The Chi-Square Distribution

Chapter 13 F Distribution and One-Way ANOVA

### Pedagogical foundation and features

**Examples**are placed strategically throughout the text to show students the step-by-step process of interpreting and solving statistical problems. To keep the text relevant for students, the examples are drawn from a broad spectrum of practical topics, including examples about college life and learning, health and medicine, retail and business, and sports and entertainment.**Try It**practice problems immediately follow many examples and give students the opportunity to practice as they read the text.**They are usually based on practical and familiar topics, like the Examples themselves**.**Collaborative Exercises**provide an in-class scenario for students to work together to explore presented concepts.**Using the TI-83, 83+, 84, 84+ Calculator**shows students step-by-step instructions to input problems into their calculator.**The Technology Icon**indicates where the use of a TI calculator or computer software is recommended.**Practice, Homework, and Bringing It Together**problems give the students problems at various degrees of difficulty while also including real-world scenarios to engage students.

### Changes to the Second Edition

The revision of *Introductory Statistics* has been undertaken with the support of hundreds of faculty adopters and student users. Most of the edits are focused on currency, relevance, accuracy, and belonging. Dozens of examples and references have been changed in order to align with contemporary contexts and uses. Data and references have been extensively updated, as well. Accuracy checking and errata resolutions resulted in corrections and clarifications, both in the main text and in the answers/solutions. Finally, the second edition includes several hundred edits related to gender, race, ethnicity, age, academic status, and societal issues, designed to present the most informed and inclusive material.

OpenStax only undertakes revisions when pedagogically necessary, and we work to ensure that the text maintains its organization in order to ease transition for instructors. Many of the above changes have been made within problems and examples. However, in nearly all cases, the problems retain their original numbering, so that instructors and online homework providers can move to the new edition with minimal impact on their assignment structures. A detailed transition guide is available on the instructor resource page for this textbook.

### Statistics labs

These innovative activities were developed by Barbara Illowsky and Susan Dean in order to offer students the experience of designing, implementing, and interpreting statistical analyses. They are drawn from actual experiments and data-gathering processes and offer a unique hands-on and collaborative experience. The labs provide a foundation for further learning and classroom interaction that will produce a meaningful application of statistics.

Statistics Labs appear at the end of each chapter and begin with student learning outcomes, general estimates for time on task, and any global implementation notes. Students are then provided with step-by-step guidance, including sample data tables and calculation prompts. The detailed assistance will help the students successfully apply the concepts in the text and lay the groundwork for future collaborative or individual work.

### Answers to Questions in the Book

Answers to Examples are provided directly under the question. Answers to Try it Questions are provided at the Student Resources page. Answers to an assortment of Practice, Homework, and Bring it Together questions are provided at the end of each chapter for students. All answers to these questions are provided for instructors in the Instructor Answer Guide via the Instructor Resources page. Due to the high variability in responses, answers to Collaborative Exercises and Labs are not provided.

## Additional resources

### Student and instructor resources

We’ve compiled additional resources for both students and instructors, including Getting Started Guides, an instructor solution manual, and PowerPoint slides. Instructor resources require a verified instructor account, which you can apply for when you log in or create your account on OpenStax.org. Take advantage of these resources to supplement your OpenStax book.

### Community Hubs

OpenStax partners with the Institute for the Study of Knowledge Management in Education (ISKME) to offer Community Hubs on OER Commons – a platform for instructors to share community-created resources that support OpenStax books, free of charge. Through our Community Hubs, instructors can upload their own materials or download resources to use in their own courses, including additional ancillaries, teaching material, multimedia, and relevant course content. We encourage instructors to join the hubs for the subjects most relevant to your teaching and research as an opportunity both to enrich your courses and to engage with other faculty.

To reach the Community Hubs, visit www.oercommons.org/hubs/OpenStax.

### Partner resources

OpenStax Partners are our allies in the mission to make high-quality learning materials affordable and accessible to students and instructors everywhere. Their tools integrate seamlessly with our OpenStax titles at a low cost. To access the partner resources for your text, visit your book page on OpenStax.org.

## About the authors

### Senior contributing authors

**Barbara Illowsky, De Anza College**

**Susan Dean, De Anza College**

### Contributing Authors

Daniel Birmajer, Nazareth College

Bryan Blount, Kentucky Wesleyan College

Sheri Boyd, Rollins College

Matthew Einsohn, Prescott College

James Helmreich, Marist College

Lynette Kenyon, Collin County Community College

Sheldon Lee, Viterbo University

Jeff Taub, Maine Maritime Academy

### Reviewers

Birgit Aquilonius, West Valley College

Charles Ashbacher, Upper Iowa University, Cedar Rapids

Abraham Biggs, Broward Community College

Roberta Bloom, De Anza College

Ernest Bonat, Portland Community College

Sarah Boslaugh, Kennesaw State University

David Bosworth, Hutchinson Community College

George Bratton, University of Central Arkansas

Jing Chang, College of Saint Mary

Laurel Chiappetta, University of Pittsburgh

Lenore Desilets, De Anza College

Ann Flanigan, Kapiolani Community College

David French, Tidewater Community College

Mo Geraghty, De Anza College

Larry Green, Lake Tahoe Community College

Michael Greenwich, College of Southern Nevada

Inna Grushko, De Anza College

Valier Hauber, De Anza College

Janice Hector, De Anza College

Robert Henderson, Stephen F. Austin State University

Mel Jacobsen, Snow College

Mary Jo Kane, De Anza College

Charles Klein, De Anza College

Alexander Kolovos

Sara Lenhart, Christopher Newport University

Wendy Lightheart, Lane Community College

Vladimir Logvenenko, De Anza College

Jim Lucas, De Anza College

Lisa Markus, De Anza College

Miriam Masullo, SUNY Purchase

Diane Mathios, De Anza College

Robert McDevitt, Germanna Community College

Mark Mills, Central College

Cindy Moss, Skyline College

Nydia Nelson, St. Petersburg College

Benjamin Ngwudike, Jackson State University

Jonathan Oaks, Macomb Community College

Carol Olmstead, De Anza College

Adam Pennell, Greensboro College

Kathy Plum, De Anza College

Lisa Rosenberg, Elon University

Sudipta Roy, Kankakee Community College

Javier Rueda, De Anza College

Yvonne Sandoval, Pima Community College

Rupinder Sekhon, De Anza College

Travis Short, St. Petersburg College

Frank Snow, De Anza College

Abdulhamid Sukar, Cameron University

Mary Teegarden, San Diego Mesa College

John Thomas, College of Lake County

Philip J. Verrecchia, York College of Pennsylvania

Dennis Walsh, Middle Tennessee State University

Cheryl Wartman, University of Prince Edward Island

Carol Weideman, St. Petersburg College

Andrew Wiesner, Pennsylvania State University