Sample Mean Formula
The sample mean formulas calculates the average value of sample data.
Formula Terms
| Expression | Description |
|---|---|
| The sample mean. | |
| The value of the element at the -th position. | |
| The number of data points |
To calculate the sample mean, sum all the data points in a sample space and then divide by the number of elements. For example, to calculate the sample mean of the sample data , sum together all of the data points and divide by the number of elements.
This example shows how to calculate the mean of a data set shown below.
Set up the formula.
Substitute the data values into the numerator and the size of the dataset into the denominator. In this case, there are six elements in the dataset so .
Calculate the sum of the values.
Calculate the result of the division.
The sample mean is .
This example shows how to calculate the mean of a data set shown below.
Start by setting up the formula.
Substitute the data values into the numerator and the size of the dataset into the denominator. In this case, there are five elements in the dataset so .
Calculate the sum of the values.
Calculate the result of the division.
The mean of the dataset is .
The population mean formula gives the average value of the whole population.