Created attachment 109462 [details]
Sample Spreadsheet showing the test

Summary:
When using the Data->Statistics->t-test menu, one can get a dialog box to auto-generate a paired t-test.
By default, the test is done with the hypothesis that the mean difference is 2 (always the number two), while in almost every case everybody wants to test the hypothesis of equal means (difference zero).
Once the table is generated, it's easy to work around this bug, by storing 0 in the cell "Hypothesized Mean Difference" (by default, it's 2).
But, it's very misleading. The hypothesized mean difference is not shown in the dialog box, and the generated "hypothesized mean difference" cell is hidden in many cells of various statistics.

Steps to reproduce:
Create two columns of numbers.
Select the data.
Go to Data->Statistics->t-test
Select an output cell
Click OK

Observed behavior:
The p-value of the test is computed based on the null hypothesis : mean((column A)-(column B)) = 2

Expected behavior:
The p-value of the test is computed based on the null hypothesis : mean((column A)-(column B)) = 0

Bugfix:
In file sc/source/ui/StatisticsDialogs/TTestDialog.cxx b/sc/source/ui/StatisticsDialogs/TTestDialog.cxx
Replace the two lines:

aOutput.writeValue(2);
aTemplate.autoReplaceAddress("%HYPOTHESIZED_MEAN_DIFFERENCE%", aOutput.current());

With:
aOutput.writeValue(0);
aTemplate.autoReplaceAddress("%HYPOTHESIZED_MEAN_DIFFERENCE%", aOutput.current());