8 PART 1 Getting Started with Biostatistics

formulas than many statistics books, we include them when they help

illustrate a concept or describe a calculation that’s simple enough to do by

hand. But if you’re a real mathophobe, you probably dread looking at any

chapter that has a math expression anywhere in it. That’s why we include

Chapter 2, “Overcoming Mathophobia” to show you how to read and

understand the basic mathematical notation we use in this book. We

cover everything from basic mathematical operations to functions

and beyond.»

» ^{If you’re in a graduate-level biostatistics course, you’ve probably already taken}

one or two introductory statistics courses. But that may have been a while ago,

and you may feel unsure of your knowledge of the basic statistical concepts.

Or you may have little or no formal statistical training but now find yourself in

a work situation where you interact with clinical researchers, participate in the

design of research projects, or work with the results from biological research.

If so, read Chapter 3, which provides an overview of the fundamental concepts

and terminology of statistics. There, you get the scoop on topics such as

probability, randomness, populations, samples, statistical inference, accuracy,

precision, hypothesis testing, nonparametric statistics, and simulation

techniques.

Doing Calculations with

the Greatest of Ease

For instructional purposes, some chapters in this book include step-by-step

instructions for performing statistical tests and analyses by hand. We include

such instruction only to illustrate the concepts that are involved in the procedure

or to demonstrate calculations that are simple to do manually.

However, we demonstrate many of the statistical functions we talk about in this

book using R, which is a free, open-source software package. If you are in a class

and assigned a particular software package to use, you will have to use that soft-

ware for the course, which may be commercial software associated with a fee.

However, if you are learning on your own, you may choose to use open-source

software, which is free. Chapter  4 provides guidance on both commercial and

free software.