Re: The naive test for equality

From: mAsterdam <>
Date: Thu, 11 Aug 2005 19:58:07 +0200
Message-ID: <42fb919a$1$11069$>

dawn wrote:
> VC wrote:

>>dawn wrote:
>>>VC wrote:
>>>>...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.

This assumes perfect and lasting information at modelling time.

> In this case, yes, but it also happens frequently where such a term is
> used the same when the analysis is done, but something changes
> (government regulation or something more subtle) that changes the
> meaning slightly for one group and not another, so that these
> differences creep in.

>>I did not claim that one can correctly
>>analyze a complex system at one go,
>>it's an iterative process of trial end error.

> and needs to be attended to for the life of the attribute name
>>Besides,  your example is *not* about naming 
>>issues (as you understand yourself)

> I thought it was about the name and def of an attribute.
>>-- presumably there
>>was no ambiguity about the "student" entity .

> There are always differences of opinion about what constitutes a
> student on a campus. Finance people often use the term as if the
> student were the same as a corporate customer. Student = Customer. If
> someone has received some approval to audit a course for zero dollars,
> the instructor might consider them a student. That is just an example,
> but the point is that entity names are also just words and are
> interpreted by humans, each of whom brings a different context to the
> meaning of the word.
> I've been reading and writing too fast lately and might have missed the
> point, so I'll re-read the thread before posting again.
> cheers! --dawn

This is a sub-thread about synonym/homonym problems, but this group does not tend to change the subject line appropriately (I tried a few times, but it did not really work). In the sub-thread your contribution is right on the mark, IMO. Received on Thu Aug 11 2005 - 19:58:07 CEST

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