You want to calculate a t-test? It's easy with DATAtab, just copy your data into the table above and select your variables for which you want to calculate the t-test! DATAtab will automatically use the appropriate test and interpret your results.
If you want to calculate a t-test with your own data online, empty the upper table (click on Empty Table), copy your own data into it and make sure that the variable name is in the first row. Afterwards the variables are displayed below the table. Now click on the variables you want to evaluate. After selecting your variables, the t-test calculator will suggest which t-test you should use. You can choose from the following options:
- Simple t-Test
- t-Test for Dependent Samples
- t-Test for Independent Samples
In the results section of the online t-test calculator you will find the mean and standard deviation of the samples and of course the calculated t-value and p-value. Which t-test you have to use is determined by the type of your sample or samples and how they are related to each other.
Simple t-Test Calculator
You want to test whether the mean of a sample is equal to that of the population? Then select a metric variable and specify the test value.
Independent t-Test Calculator
You want to compare the means of two independent groups? Then select two metric variables or one metric variable and one nominal variable with two values.
Dependent t-Test Calculator
You want to compare two groups where the measured values belong together in pairs? Then select two metric variables.
Of course you also get the p-value calculated and displayed in a table. t-Test calculator p-value
You can specify the significance level right at the beginning of the calculation. If you want to calculate a one-sided t-test, you can either specify this as well or you simply divide your p-value by two at the end.
More information about the theory behind the t-test and detailed examples can be found here:
In order to calculate the p-value, the t-value must first be calculated. The p-value is then calculated from the t-value and the degrees of freedom.