Statistics Essentials For Dummies

Chapter 2

Descriptive Statistics

IN THIS CHAPTER

Statistics to measure center

Standard deviation, variance, and other measures of spread

Measures of relative standing

Descriptive statistics are numbers that summarize some characteristic about a set of data. They provide you with easy-to-understand information that helps answer questions. They also help researchers get a rough idea about what’s happening in their experiments so later they can do more formal and targeted analyses. Descriptive statistics make a point clearly and concisely.

In this chapter, you see the essentials of calculating and evaluating common descriptive statistics for measuring center and variability in a data set, as well as statistics to measure the relative standing of a particular value within a data set.

Types of Data

Data come in a wide range of formats. For example, a survey might ask questions about gender, race, or political affiliation, while other questions might be about age, income, or the distance you drive to work each day. Different types of questions result in different types of data to be collected and analyzed. The type of data you have determines the type of descriptive statistics that ...