## T tests

Let's start with t tests. A sample t test gives you a leverage point to check whether the sample mean that can have a normally distributed variable has a significant difference from the hypothesis value. For example, you need to test whether the fridge sales average is significantly different from `10000`

. Here is the command to run the t test:

**ttest fridge_sales = 10000**

This command checks whether the mean or average of `fridge_sales`

differs significantly from `10000`

. Here is the exact formula for a sample t test:

Here are the results of **One-sample t test** as per the command that's run in Stata:

This result shows that there is a statistically significant difference between the mean values of **fridge_sales** and **10000**. Let's see whether you have more than one group to compare the means. In this case, you can use two independent sample t-tests.

### Two independent sample t tests

Independent samples' t tests are utilized when we need to compare and check the averages of a variable that is normally...