# One sample t-test in SPSS

May 17, 2019

Running a one-sample t-test in **SPSS** is very straight forward. For the purpose of this example, let’s use the *demo.sav* training dataset. From the top menu, select *Analyze >> Compare Means >> One-Sample T Test…*.

Now you’ll be presented with a window for choosing a variable to test, for example *Job satisfaction*. It seems to run from 1 - 5, I’ll just take a wild guess and say that the sample average is 2 or that’s the level of average job satisfaction. So let’s put in 2 the box for *Test Value*:

Now let’s hit **OK** to run the test. We’re now presented with a results window, like so:

Ok, so here we stated that the null hypothesis is *the sample mean is equal to 2*. The guess was apparently a bit off as the sample mean was actually **3.06**. The significance values of .000 also tells us to react the null hypothesis. Moreover, the 95% confidence interval suggests that the mean lie within 1.02 - 1.09 from the test value, in other words somewhere between 3.02 - 3.09.

Written by **Johan Osterberg** who lives and works in Gothenburg, Sweden as a developer specialized in e-commerce. Connect with me on Linkedin