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> Thanks for the feedback. As to your point 1, I freely admit the
> failing. It is an area I am currently working on, and still need
I think instead that people who hide behind insults do that because are scared to do an open confrontation with scientific arguments.
I am always ready to confront and admit my errors because I have a sincere love for what is right and I have no problem if this is stated by another person.
Ok I found this reference:
http://www.latrobe.edu.au/philosophy/phimvt/joy/j04alg.html
"Idempotency, zero elements and arities"
A binary function f(x,y) is called idempotent if for all x
f(x,x) = x
According to the above definition:
countDistinct (5,6) = 2
countDistinct is "not idempotent" (1 counterexample is enough)
max(x,x) = x for any x
max is "idempotent"
(1) Your statement is: "Duplication Sensitive" <=> Non Idempotent
if we negate both sides, we obtain an equivalent statement:
(2) "Not Duplication Sensitive" <=> Idempotent
Now observe that CountDistinct is "Not Duplication Sensitive function" example: CountDistinct (2,2) = 1.
At the same time CountDistinct is "not idempotent" (see above).
Therefore we have found 1 case where:
(3) "Not Duplication Sensitive function" => "idempotent"
is false. Therefore (2), (1) are false.
(The inverse implication of (3) is clearly true)
Do you see errors in the above argument?
-P Received on Sun Sep 17 2006 - 16:59:41 CDT
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