Mean, Median and Mode: Which Average Should You Use?

"Average" can mean three different things in statistics.

Mean

Add the values and divide by how many there are: $\bar{x}=\frac{1}{n}\sum x_i$.

Median

Sort the data; the median is the middle value (or the average of the two middle values).

Mode

The value that appears most often. A data set can have no mode or several.

Example

Salaries (in $1000s): 32, 35, 38, 40, 41, 250.

• Mean: $\frac{436}{6}\approx 72.7$
• Median: $\frac{38+40}{2}=39$

One extreme salary drags the mean far above what a typical person earns. When data is skewed or has outliers, report the median.

Compute all three (plus standard deviation and quartiles) with the Statistics Calculator.