# VSEM function

## Description

VSEM(variable[,filter]) returns the standard error of the mean of a variable. An optional filter can be specified.

The Standard Error of the Mean (SEM) is calculated as follows:

$$SEM = \frac{s}{\sqrt{n}} $$

where * s* is the standard deviation:

$$s = \sqrt{\frac{\sum_{}^{}{(x-\bar{x})^2}}{n-1}} $$

## Example

## Note

This function calculates a statistic on a variable. Be careful when you use this function in cells of the columns that correspond to the variable, because this actually adds a value to the variable which can lead to unexpected and faulty results. You can exclude the cell to avoid this.