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Re: The naive test for equality

From: VC <>
Date: Thu, 11 Aug 2005 07:02:12 -0400
Message-ID: <>

"dawn" <> wrote in message
> VC wrote:

>> You are kidding, right ? If the modellers chose the name/label "source"
>> and
>> did not define what entity the name refers to, then the name is just
>> meaningless, like say "fshsalkfd". Apparently, your hypothetical
>> modellers
>> are not modellers but some kind of impostors.
> It is usually much more subtle than that. Everyone agrees that we need
> to know whether or not someone is a fullTimeStudent. Ignore the fact
> that this would likely be a derived attribute -- it illustrates the
> problem. After some sessions with folks from many departments, the
> analyst works to get more precision and sits down with someone who
> knows all of the tuition rules, along with another person ('cause the
> analyst is no rookie) and they nail down this attribute with the
> precision of a surgeon.
> The system goes live and the financial aid people are irate! Federal
> aid has just been removed from students because they were no longer
> flagged as being a fullTimeStudent when by the standards for this
> financial aid, they clearly ARE a fullTimeStudent.
> Then you find out that these two departments use the very same term and
> might even both have external reasons to use the very same term, and
> they use it with just slightly different meanings.

Apparently, the analysts made a mistake in assuming that the set of fullTimeStudents is equal to the set of studentsEligibleForFinancialAid. I did not claim that one can correctly analyze a complex system at one go, it's an iterative process of trial end error. Besides, your example is *not* about naming issues (as you understand yourself) -- presumably there was no ambiguity about the "student" entity .

> It does help if there is a well-maintained and easily used catalog /
> dictionary / metadata repository. But words are just that. --dawn
Received on Thu Aug 11 2005 - 06:02:12 CDT

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