The Sign test is a nonparametric alternative to the t-test for dependent samples. The test is applicable to situations when the researcher has two measures (e.g., under two conditions) for each subject and wants to establish that the two measurements (or conditions) are different.

This is an example of comparing two dependent samples using a Sign test; also it shows how to draw a Box and Whisker blot with Statistica.

1. Go to "File | Open Examples" | Datasets | Synchron.sta

2. Click on "Nonparametics" under "Statistica" tab

3. On the "Quick" tab, select "Comparing two dependent samples (variables)", and click the “OK” button

4. Click on "Variables" to display the standard variable selection dialog box. In the "First variable" list, select variable In_Sync; from the "Second variable" list, selectOut_Sync, and then click OK.

5.  Click on "Sign test" button to begin the desirous analysis:

6. A box and whisker plot can also be generated by clicking on the "Box & whisker plots" for all variables button:

7. Click the OK button to produce the graph.