Introduction

Good news! You don’t have to know diddlysquat about the math behind statistics to be able to come up with well-calculated conclusions and display them in fancy graphs. You won’t be doing any calculations by hand. All you need is the IBM SPSS Statistics software and a bunch of numbers. This book shows you how to type the numbers, select options in the menus, and produce brilliant statistics. And interpret them properly, too! It really is as simple as that.

About This Book

Some sections of the book are written as stand-alone tutorials to make it easy for you to get into whatever you’re after. After you’re up and running with SPSS, you can skip around and read just the sections you need. You really don’t need to read straight through the entire book. However, the book's chapters are organized in parts, and it's generally a good idea to read the chapters in a part in sequence. And you should start with Part 1 if you are brand new to SPSS.

This book is not about math. It’s about statistics. You don’t derive anything. You don’t do any math by hand or look up numbers in statistical tables. You won’t find one explanation of how calculations are performed under the hood. This book is about the things you can do to command SPSS to calculate statistics for you. You can avoid all of those fancy formulas with lots of sigmas in them and still use SPSS to produce some nifty stats!

However, if you decide to study the techniques of statistical calculation, you’ll be able to understand what SPSS does to produce numbers. Your main advantage in understanding the process to that degree of detail is that you’ll be able to choose a calculation method that more closely models the reality you’re trying to analyze. Although SPSS rescues you from the stress that some associate with manual calculations, it still leaves it up to you to interpret the results. We spend a lot of pages on carefully preparing you for that responsibility.

Throughout the book are examples that use data stored in files. These files are freely available to you. Some files are installed with IBM SPSS Statistics in the SPSS installation directory, which is \Program Files\SPSS (unless you chose another location during installation). Other files are available via the Welcome dialog when you launch SPSS. Most of the files, however, were designed for this book and are available on the book's companion website (see “Beyond the Book” for more information). In every case, the files were carefully curated to demonstrate some specific capability of SPSS.

And a technical note: The official name of the product is IBM SPSS Statistics. Throughout this book, we refer to it simply as SPSS. Outside this book, that shortcut can be risky because other related products are also called SPSS — notably, IBM SPSS Modeler, which, though powerful and part of the same brand, is not the subject of this book.

About the Fourth Edition

The authors wrote this fourth edition using IBM SPSS Statistics version 27. The technical editor checked all tasks against his concurrent version of SPSS Statistics Subscription and the instructions were consistent on both platforms. The third edition of this book was written using IBM SPSS Statistics version 23. Even if you use a version of SPSS prior to version 27, we urge you to use this fourth edition because its more than 100 pages of new content better prepare new users and meet the needs of intermediate users, as well as cover statistical analytic procedures to a much greater extent.

Foolish Assumptions

This book is for anyone new to SPSS. No prior knowledge of statistics is needed or even expected. In specific terms, we made a few assumptions about you, the reader of this book:

  • You may be a student who isn’t majoring in statistics but has been instructed to use SPSS by one of your professors.
  • You may have an interest in statistical analysis but are new to using SPSS.
  • You may work in an office setting and have been asked to use SPSS to analyze some data.

For most people who generate statistics, the complexity of using the software becomes an obstacle. Our purpose in writing this book is to show you how to move that obstacle out of the way with minimum effort.

Icons Used in This Book

Throughout this book, we use icons in the margins to grab your attention. Here’s what those icons mean:

Remember You should keep this information in mind. It’s important to what you’re doing.

Technical stuff This icon highlights unnecessarily geeky information, but we had to include it to complete the thought. You can skip anything marked with this icon unless the text makes you curious.

Tip This icon highlights a point that can save you time and effort.

Warning Anything marked with this icon offers information about something that can sneak up and bite you.

Beyond the Book

In addition to the material in the print or e-book you’re reading right now, this product also comes with some access-anywhere goodies on the web. Check out the free cheat sheet at www.dummies.com/cheatsheet/spss for information on variable levels of measurement, commonly used procedures in the Analyze menu, and possible conclusions that you can reach after conducting a statistical test. Finally, for the examples, you can download the data files that don’t come with SPSS at www.dummies.com/go/spss or keithmccormick.com/SSFD4E.

Where to Go from Here

If you're new to SPSS, we recommend starting out by reading Part 1, so you understand what SPSS is. If you haven’t already gained access to a copy of SPSS, check out Chapter 2. Chapter 3 introduces the software and goes through a typical session using SPSS. Read the stuff in Chapter 4 about defining variables and declaring metadata — it all makes sense once you get the hang of it, but the process seems kind of screwy until you see how it works. The material in Chapter 4 covers areas in which some new users of SPSS go astray, so read it carefully. And from there, use the table of contents and index to find the things you want to do!

Two chapters are worthy of special mention. Chapter 22 helps you navigate statistical techniques covered in Parts 5 and 6 and beyond. If you know the name of the statistical procedure you want to use, you should be okay without Chapter 22. But what if you don’t know the name of the statistical procedure? How are you supposed to look it up? This is when you should try Chapter 22.

Sometimes things seem amiss, but you simply don’t know what's wrong. Chapter 30 addresses this issue. How are you supposed to find out how to fix an issue when SPSS isn’t working as it’s supposed to? In this case, check out Chapter 30, which covers the most common reasons why SPSS acts strangely.

If you have a question, you can reach Jesus Salcedo at jesussalcedo@yahoo.com and Keith McCormick at keithmc123@keithmccormick.com. We will post information about updates, joining our mailing list, and the latest SPSS news at keithmccormick.com/SSFD4E.