Hi Helmut,

» WinNonlin 5.2.1
»   STDEV(90000001;90000002;90000003) = 0

Just saw your post on this - I managed to replicate it in a workbook using a cell formula, however this is not how I'd recommend people perform such data manipulations in WinNonlin.

Performing the same calculation using either Descriptive Stats or the summary stats within Table Wizard will give you the correct answer i.e. 1. (as indeed will your worked example of calculating it without using the SD function).

I would recommend any WinNonlin users to use the Tools functions I described above since the 'grid' calculations come from, I think FormulaOne, which is a third party tool we use that seems to be susceptible to this error. Incidentally I don't think this should be a problem with Version 6 since it's not using this data grid anymore.

Cheers,
Simon

Simon
Senior Scientific Trainer, Certara™
https://www.certarauniversity.com/dashboard
https://support.certara.com/forums/