In an increasingly data-driven world, it is more important than ever for students as well as professionals to better understand basic statistical concepts. 100 Questions (and Answers) About Statistics addresses the essential questions that students ask about statistics in a concise and accessible way. It is perfect for instructors, students, and practitioners as a supplement to more comprehensive materials, or as a desk reference with quick answers to the most frequently asked questions.

# What Is the Mean, and How Is It Computed?

### What Is the Mean, and How Is It Computed?

The mean is the most commonly used measure of central tendency. It is the sum of all the values in a group divided by the number of values in the group. A more technical definition is that the mean is the point about which the sum of the deviations equals zero. The type of mean we are discussing here is also called the arithmetic mean.

The formula is quite simple, as follows.

$\overline{X}=\frac{\sum X}{n}$

where

• $\overline{X}$ equals the mean,
• X is the sum of all the scores, and
• n is the sample size.

Note: In statistics, a lowercase n is used to represent the sample size, and an uppercase N is used to represent the population size.

To compute the mean, follow these steps:

• List ...
• • • 