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Statistics For Dummies, 2nd Edition
✓ It includes interesting real-world examples relating to your everyday life
and workplace.
✓ It gives you upfront and honest answers to your questions like, “What
does this really mean?” and “When and how will I ever use this?”
Conventions Used in This Book
You should be aware of three conventions as you make your way through
this book:
✓ Definition of sample size (n): When I refer to the size of a sample, I mean
the final number of individuals who participated in and provided informa-
tion for the study. In other words, n stands for the size of the final data set.
✓ Dual-use of the word statistics: In some situations, I refer to statistics
as a subject of study or as a field of research, so the word is a singular
noun. For example, “Statistics is really quite an interesting subject.” In
other situations, I refer to statistics as the plural of statistic, in a numeri-
cal sense. For example, “The most common statistics are the mean and
the standard deviation.”
✓ Use of the word data: You’re probably unaware of the debate raging
amongst statisticians about whether the word data should be singular
(“data is . . .”) or plural (“data are . . .”). It got so bad that recently one
group of statisticians had to develop two different versions of a statis-
tics T-shirt: “Messy Data Happens” and “Messy Data Happen.” At the risk
of offending some of my colleagues, I go with the plural version of the
word data in this book.
✓ Use of the term standard deviation: When I use the term standard
deviation, I mean s, the sample standard deviation. (When I refer to the
population standard deviation, I let you know.)
Here are a few other basic conventions to help you navigate this book:
✓ I use italics to let you know a new statistical term is appearing on the scene.
✓ If you see a boldfaced term or phrase in a bulleted list, it’s been desig-
nated as a keyword or key phrase.
✓ Addresses for Web sites appear in monofont.

What You’re Not to Read

I like to think that you won’t skip anything in this book, but I also know you’re
a busy person. So to save time, feel free to skip anything marked with the

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