Chapter 1

Statistics in a Nutshell


Bullet Getting the big picture of the field of statistics

Bullet Overviewing the steps of the scientific method

Bullet Seeing the role of statistics at each step

The most common description of statistics is that it’s the process of analyzing data — number crunching, in a sense. But statistics is not just about analyzing the data. It’s about the whole process of using the scientific method to answer questions and make decisions. That process involves designing studies, collecting good data, describing the data with numbers and graphs, analyzing the data, and then making conclusions. In this chapter, I review each of these steps and show where statistics plays the all-important role.

Designing Studies

Once a research question is defined, the next step is designing a study in order to answer that question. This amounts to figuring out what process you’ll use to get the data you need. In this section, I overview the two major types of studies: observational studies and experiments.


An observational study is one in which data are collected on individuals in a way that doesn’t affect them. The most common observational study is the survey. ...

Get Statistics Essentials For Dummies now with the O’Reilly learning platform.

O’Reilly members experience books, live events, courses curated by job role, and more from O’Reilly and nearly 200 top publishers.