CHAPTER 8

Design of a Study: Sampling, Surveys, and

Experiments

IN THIS CHAPTER

Summary: This chapter stands pretty much alone in this course. All other chapters are concerned with
how to analyze and make inferences from data that have been collected. In this chapter, we discuss how to
collect the data. Doing an analysis of bad or poorly collected data has no practical application. Here
you’ll learn about surveys and sampling, observational studies, experiments, and the types of bias that can
creep into each of them. Once you understand all this, you’ll have greater confidence that your analysis
actually represents something more than meaningless number crunching.

Key Ideas

Samples and Sampling

Surveys

Sampling    Bias

Experiments and Observational   Studies

Statistical Significance

Completely  Randomized  Design

Matched Pairs   Design

Blocking

Samples

In the previous two chapters we concentrated on the analysis of data at hand—we didn’t worry much