A First Course in Statistics, 12th Edition

2.3 Numerical Measures of Central Tendency

When we speak of a data set, we refer to either a sample or a population. If statistical inference is our goal, we’ll ultimately wish to use sample numerical descriptive measures to make inferences about the corresponding measures for a population.

As you’ll see, a large number of numerical methods are available to describe quantitative data sets. Most of these methods measure one of two data characteristics:

1. The central tendency of the set of measurements—that is, the tendency of the data to cluster, or center, about certain numerical values. (See Figure 2.14a.)

   

   Figure 2.14

   Numerical descriptive ...