Chapter 3. Descriptive Statistics
When summarizing and describing numerical variables you need to do more than just prepare the tables and charts discussed in Chapter 2, “Presenting Data in Charts and Tables.” In reading this chapter, you can learn some of the descriptive measures that identify the properties of central tendency, variation, and shape.
3.1 Measures of Central Tendency
Because the data values of most numerical variables show a tendency to group around a specific value, statisticians use a set of methods, collectively known as measures of central ...