From: | Bruno Wolff III <bruno(at)wolff(dot)to> |
---|---|
To: | Csaba Nagy <nagy(at)ecircle-ag(dot)com> |
Cc: | Martijn van Oosterhout <kleptog(at)svana(dot)org>, pgsql-hackers(at)postgresql(dot)org |
Subject: | Re: [OT] somebody could explain this? |
Date: | 2005-11-04 17:53:43 |
Message-ID: | 20051104175343.GA12968@wolff.to |
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Lists: | pgsql-hackers |
On Fri, Nov 04, 2005 at 18:30:56 +0100,
Csaba Nagy <nagy(at)ecircle-ag(dot)com> wrote:
> [snip]
> > Floating points numbers are accurate but not precise.
>
> OK, now this one beats me... what's the difference between "accurate"
> and "exact" ? I thought both mean something like "correct", but precise
> refers to some action and accurate applies to a situation or
> description...
>
> I'm actually curios what it means. Merriam-Webster refers for both to
> "correct" as a synonym.
My memory from science courses a long time ago, is that precision refers
to how much information you have (e.g. the number of digits in a number)
and accuracy refers to how close your information is to reality.
Using a precision that was much higher than justified by accuracy used to
get points deducted from lab report grades.
In mathematics "precise" has a somewhat different meaning, but isn't a synonym
for "accurate" in that context.
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