Craig McLean wrote:

> Can you be more specific? A search of wiki.apache.org/spamassassin shows
> 2 pages containing "rounding":
> StatusRounding - orphaned.
> RoundingIssues - this is not the issue I'm talking about, and in any
> case was fixed in 3.0.

Actually if you read:
http://wiki.apache.org/spamassassin/RoundingIssues

Your particular case would be MAGNIFIED by the bugfix, not corrected by it.

SA 2.6x used normal rounding when printing numbers (ie: 0.06 rounds to 0.1, 0.04
rounds to 0).

With 2.6 it was possible for the hits to look like they should have been higher
than they are. (ie: rounded numbers add up to 5.0, but the total score is 4.9).
It was also possible for then to look like they should be lower. Normal rounding
does that. Sometimes you round up, sometimes down.

SA 3.0 "fixes" this by always rounding down (0.06 rounds to 0). This doesn't
really "fix" anything, as to "fix" it would be impossible. It does however shift
the nature of the problem around.

Now you'll never see a total that looks too low. Now you'll only ever see ones
that look to high. You'll also see on average more "errors" as there's never any
chance for two rounded numbers to cancel each other out. They' also on average
be more severe in magnitude.

Any form of rounding introduces error. You can force that error to always be on
the low side (round down), always on the high side (round up), or split between
the two (normal rounding). It's a matter of picking which of the three is better
understood by users (and really, the average user doesn't understand this kind
of thing at all, so you're pretty much screwed no matter what you do)

The only way to truly "fix" the "bug" is to print the whole, unrounded score for
everything. But that creates a very cluttered report, which would be another 
bug.

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