https://bugs.freedesktop.org/show_bug.cgi?id=61512

          Priority: medium
            Bug ID: 61512
          Assignee: libreoffice-bugs@lists.freedesktop.org
           Summary: Calc ROUND() don't use default IEEE 754 method (->
                    statistical error).
          Severity: normal
    Classification: Unclassified
                OS: All
          Reporter: lo_b...@web.de
          Hardware: All
            Status: UNCONFIRMED
           Version: unspecified
         Component: Libreoffice
           Product: LibreOffice

Why doesn't Calc'S ROUND() use the mathematical/statistical correct rounding
method that is also the default IEEE 754 standard for floating point numbers?

https://en.wikipedia.org/wiki/IEEE-754#Roundings_to_nearest
https://en.wikipedia.org/wiki/Rounding#Round_half_to_even

Example:
=ROUND(5/2) gives "3"
its should give "2" however, if it used the correct computer/statistics
rounding, because on a plain ".5(0000...)" you have to round to the even number
to avoid statistical errors.

More example: If you average over 1000 rounded positive half integers (-> the
mean of 1000 random round(n/2) ) it will be simply wrong, because for all odd n
you will round up, but it will never happen that you round down. Your mean will
be to big.

That's why Calc should have a ROUND() that uses statistical/mathematical and
standard correct rounding.

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