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

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#### Art Attribution in *Statistics*

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#### Format

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### About *Statistics*

This instructional material was initially created through a Texas Education Agency (TEA) initiative to provide high-quality open-source instructional materials to districts free of charge. Funds were allocated by the 84th Texas Legislature (2015) for the creation of state-developed, open-source instructional materials with the request that advanced secondary courses supporting the study of science, technology, engineering, and mathematics should be prioritized.

*Statistics* covers the scope and sequence requirements of a typical one-year statistics course. The text provides comprehensive coverage of statistical concepts, including quantitative examples, collaborative activities, and practical applications. *Statistics* was designed to meet and exceed the requirements of the relevant Texas Essential Knowledge and Skills (TEKS), while allowing significant flexibility for instructors.

Qualified and experienced Texas faculty were involved throughout the development process, and the textbooks were reviewed extensively to ensure effectiveness and usability in each course. Reviewers considered each resource’s clarity, accuracy, student support, assessment rigor and appropriateness, alignment to TEKS, and overall quality. Their invaluable suggestions provided the basis for continually improved material and helped to certify that the books are ready for use. The writers and reviewers also considered common course issues, effective teaching strategies, and student engagement to provide instructors and students with useful, supportive content and drive effective learning experiences.

#### Coverage and Scope

*Statistics* presents the appropriate statistical concepts and skills in a logical and engaging progression that should be familiar to faculty.

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

#### Flexibility

Like any OpenStax content, this textbook can be modified as needed for use by the instructor depending on the needs of the students in the course. Each set of materials created by OpenStax is organized into units and chapters and can be used like a traditional textbook as the entire syllabus for each course. The materials can also be accessed in smaller chunks for more focused use with a single student or an entire class. Instructors are welcome to download and assign the PDF version of the textbook through a learning management system or can use their LMS to link students to specific chapters and sections of the book relevant to the concept being studied. The entire textbook will be available during the fall of 2020 in an editable Google document, and until then instructors are welcome to copy and paste content from the textbook to modify as needed prior to instruction.

#### Student-Centered Focus

*Statistics* was developed with detailed and practical guidance from experienced high school teachers and curriculum experts. Their contributions helped create a resource that provides easy-to-follow explanations with ample opportunities for enrichment and practice. In addition to clear and grade-level appropriate main text coverage, the following features are meant to enhance student understanding of statistics concepts:

*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 from academic 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. Like the Examples, the Try It problems are usually based on practical and familiar topics.*Collaborative Exercises*provide an in-class scenario for students to work together and learn from each other as they explore course concepts.*Calculator Guidance*shows students step-by-step instructions for input using the TI-83, 83+, 84, and 84+ calculators and helps them consider how to use these tools in their studies. 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 including real-world scenarios to engage students.

#### Statistics Labs

These innovative activities were developed by Barbara Illowsky and Susan Dean (both of De Anza College) and allow students to design, implement, and interpret statistical analyses. They are drawn from actual experiments and data-gathering processes and offer a unique hands-on and collaborative experience. Statistics Labs appear at the end of each chapter and begin with student learning outcomes, general estimates for time on task, and global implementation notes. Students are then provided with step-by-step guidance, including sample data tables and calculation prompts. This detailed assistance will help the students successfully apply statistics concepts and lay the groundwork for future collaborative or individual work.

#### Answers to Questions in the Book

Answers to Examples are provided directly below the question. Try It solutions are not provided. Students can find answers to odd-numbered Practice, Homework, and Bringing it Together questions at the end of each chapter, and all answers to Review Problems and Practice Test questions in Appendix A and B. Answers to even-numbered Practice, Homework, and Bringing it Together questions are provided only to instructors in the Instructor Answer Guide via the Instructor Resources page.

### Additional Resources

#### Student and Instructor Resources

We’ve compiled additional resources for both students and instructors, including Getting Started Guides, PowerPoint slides, and an instructor answer guide. 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.

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### 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 of Prior Editions

Laurel Chiappetta, University of Pittsburgh

Lenore Desilets, De Anza College

Lisa Markus, De Anza College

Mary Teegarden, San Diego Mesa College

Carol Olmstead, De Anza College

Carol Weideman, St. Petersburg College

Charles Ashbacher, Upper Iowa University, Cedar Rapids

Charles Klein, De Anza College

Cheryl Wartman, University of Prince Edward Island

David French, Tidewater Community College

Dennis Walsh, Middle Tennessee State University

Diane Mathios, De Anza College

John Thomas, College of Lake County

Jing Chang, College of Saint Mary

Sara Lenhart, Christopher Newport University

Sarah Boslaugh, Kennesaw State University

Abdulhamid Sukar, Cameron University

Abraham Biggs, Broward Community College

Adam Pennell, Greensboro College

Alexander Kolovos

Ann Flanigan, Kapiolani Community College

Robert McDevitt, Germanna Community College

Roberta Bloom, De Anza College

Rupinder Sekhon, De Anza College

Sudipta Roy, Kankakee Community College

Cindy Moss, Skyline College

Ernest Bonat, Portland Community College

Kathy Plum, De Anza College

Andrew Wiesner, Pennsylvania State University

Jonathan Oaks, Macomb Community College

Michael Greenwich, College of Southern Nevada

Miriam Masullo, SUNY Purchase

Mo Geraghty, De Anza College

Larry Green, Lake Tahoe Community College

Nydia Nelson, St. Petersburg College

Philip J. Verrecchia, York College of Pennsylvania

Robert Henderson, Stephen F. Austin State University

Benjamin Ngwudike, Jackson State University

Mel Jacobsen, Snow College

Birgit Aquilonius, West Valley College

Jim Lucas, De Anza College

David Bosworth, Hutchinson Community College

Frank Snow, De Anza College

George Bratton, University of Central Arkansas

Inna Grushko, De Anza College

Janice Hector, De Anza College

Javier Rueda, De Anza College

Lisa Rosenberg, Elon University

Mark Mills, Central College

Mary Jo Kane, De Anza College

Travis Short, St. Petersburg College

Valier Hauber, De Anza College

Vladimir Logvenenko, De Anza College

Wendy Lightheart, Lane Community College

Yvonne Sandoval, Pima Community College

#### Editorial Review Board

**Linda Gann** (6-12 Mathematics Coordinator, Boerne ISD) taught mathematics and statistics for over twenty-five years at Northside ISD, and currently serves as the 6-12 Mathematics Coordinator in Boerne ISD. She was awarded the Presidential Award for Excellence in Teaching, the Radio Shack National Teacher Award, the HEB Teaching Excellence Award (State Finalist), and the AP Siemens Award. For many years, Linda worked for the College Board as a consultant for AP Calculus AB, BC, and Statistics, and as a reader for AP Statistics. She has also served as the co-chair for the College and Career Readiness Standards for Mathematics for all three writing phases. Her educational background consists of a B.S. in Mathematics from Illinois State University and an M.S. in Mathematics from the University of Texas, San Antonio. Additionally, she is nearing completion of her Ph.D. in Interdisciplinary of Learning and Teaching from UTSA. She presently serves as president of the Alamo District Council of Teachers of Mathematics and scholarship chair for the Priest Holmes Foundation.

**Wendy Martinez** (Cedar Park High School) has been a teacher since 1994. She currently teaches PreAP Geometry and on-level Statistics at Cedar Park High School in Leander ISD. She has taught at Rouse High School, Lake Travis High School, and Pflugerville Middle School.

**Alexander Teich** (Rice University Graduate Student, Master’s Degree in Applied Mathematics) has teaching experience back to 2004 and has taught math classes at Spring Woods High School, in Cambridge, Massachusetts, and Philadelphia, Pennsylvania. He formerly sponsored the Spring Wood Chess Club, and has a wealth of varied practical experience outside the classroom.

**Amanda Yowell** (Pleasant Grove High School) earned a Bachelors of Science in Business Administration and Finance from the University of Arkansas and worked in Financial Management. She teaches Mathematics classes at Pleasant Grove High School in Texarkana, TX. In her free time, she enjoys spending time with her husband and their three children.