Deborah J. Rumsey - Statistics Essentials for Dummies

Statistics Essentials For Dummies

Published by: John Wiley & Sons, Inc., 111 River Street, Hoboken, NJ 07030-5774, www.wiley.com

Copyright 2019 by John Wiley & Sons, Inc., Hoboken, New Jersey

Published simultaneously in Canada

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Library of Congress Control Number: 2019937507

ISBN 978-1-119-59030-9 (pbk); ISBN 978-1-119-59024-8 (ebk); ISBN 978-1-119-59023-1 (ebk)

1. Chapter 2
2. Chapter 3
3. Chapter 4
4. Chapter 7
5. Chapter 8
6. Chapter 10
7. Chapter 11
8. Appendix

1. Chapter 3
2. Chapter 5
3. Chapter 6
4. Chapter 8
5. Chapter 9
6. Chapter 10

This book is designed to give you the essential, nitty-gritty information typically covered in a first semester statistics course. Its bottom-line information for you to use as a refresher, a resource, a quick reference, and/or a study guide. It helps you decipher and make important decisions about statistical polls, experiments, reports, and headlines with confidence, being ever aware of the ways people can mislead you with statistics, and how to handle it.

Topics I work you through include graphs and charts, descriptive statistics, the binomial, normal, and t-distributions, two-way tables, simple linear regression, confidence intervals, hypothesis tests, surveys, experiments, and of course the most frustrating yet critical of all statistical topics: sampling distributions and the Central Limit Theorem.

This book departs from traditional statistics texts and reference/supplement books and study guides in these ways:

• Clear and concise step-by-step procedures that intuitively explain how to work through statistics problems and remember the process.
• Focused, intuitive explanations empower you to know youre doing things right and whether others do it wrong.
• Nonlinear approach so you can quickly zoom in on that concept or technique you need, without having to read other material first.
• Easy-to-follow examples reinforce your understanding and help you immediately see how to apply the concepts in practical settings.
• Understandable language helps you remember and put into practice essential statistical concepts and techniques.

I refer to statistics in two different ways: as numerical results (such as means and medians) or as a field of study (for example, Statistics is all about data.).

The second convention refers to the word data. Im going to go with the plural version of the word data in this book. For example data are collected during the experiment not data is collected during the experiment.

I assume youve had some (not necessarily a lot of) previous experience with statistics somewhere in your past. For example, you can recognize some of the basic statistics such as the mean, median, standard deviation, and perhaps correlation; you can handle some graphs; and you can remember having seen the normal distribution. If its been a while and you are a bit rusty, thats okay; this book is just the thing to jog your memory.

If you have very limited or no prior experience with statistics, allow me to suggest my full-version book, Statistics For Dummies, to build up your foundational knowledge base. But if you are someone who has not seen these ideas before and either doesnt have time for the full version, or you like to plunge into details right away, this book can work for you.

I assume youve had a basic algebra background and can do some of the basic mathematical operations and understand some of the basic notation used in algebra like x, y, summation signs, taking the square root, squaring a number, and so on. (If youd like some backup on the algebra part, I suggest you consider Algebra I For Dummies and Algebra II For Dummies [Wiley]).

Here are the road signs youll encounter on your journey through this book:

Tips refer to helpful hints or shortcuts you can use to save time.