### 1. Descriptive Statistics: Measures of Central Tendency

### Introduction to Central Tendency

The main purpose of descriptive statistics is to summarize sample data in such a way that it becomes easier for the researcher to identify patterns in the data. One particularly useful way in which a distribution of scores can be summarized is to identify where the center of the distribution is located. To determine the location of the center of a distribution, a number of measures of *central tendency *can be calculated.

Central Tendency

**Definition**

**Central tendency **is a statistical measure that is used to identify a single score that describes the center of a distribution.

The purpose of central tendency is to find a *typical* or *average* score that best represents the entire distribution.

**Measures**

\[\begin{array}{rl}

\boldsymbol{\tiny{\bullet}}&\text{Mode}\\

\boldsymbol{\tiny{\bullet}}&\text{Median}\\

\boldsymbol{\tiny{\bullet}}&\text{Mean}\\

\end{array}\]

#\phantom{0}#

The coming sections will introduce the following three measures of central tendency: the *mode*,* median*, and *mean*. Each of these measures defines the center of a distribution in a different way and depending on the circumstances one measure might be more appropriate than the others.