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Re: Two examples of semi structured data.

From: mAsterdam <>
Date: Tue, 24 Aug 2004 01:19:36 +0200
Message-ID: <412a7b8d$0$25965$>

Jan Hidders wrote:
> mAsterdam wrote:

>>Jan Hidders wrote:
>>>mAsterdam wrote:
>>>>Jan Hidders wrote:
>>>>>mAsterdam wrote:
>>>>>[...] Serge argues that sometimes, from a particular viewpoint [...]
>>>>>you are really not interested in any structure that may or may not be
>>>>>hidden in a particular stream of bits; they are just a stream of bits
>>>>>and that's it.
>>>>That's it. No data, right? Signs.

> [...] It is nowhere claimed that there is data
> that is meaningless from *all* perspectives.

Of course not. Who would claim such a thing? What is meaningful to some is rubbish to others. Say a database is "a logically coherent collection of related real-world data". Surely not all data must be meaningful to all of it's users - so either there must be something (a perspective?) to unify those perspectives - or we are talking multiple databases - which of course some may find very interesting, but doesn't have my particular attention unless I'm getting paid for it.

>>Well, then let's try to talk about informationbases - hmm... doesn't
>>sound good. Nah database is fine, C<provided the data means something> -
>>thus departing from this habit.

> Hmm, no, I would also disagree there. The database does contain data which
> in turn carries information. What this information is may or may not be
> of concern to the database. So from that perspective it is indeed
> primarily a collection of data. Also note that if it becomes more
> important what the information is then the term knowledge base becomes
> more appropriate, which is largely synonymous with information base.

Yep, the word inflation rate competes with the money inflation rate.

>>>>[...] The only structure we now know is structure imposed on the signs
>>>>to be stored or forwarded or represented. This structure does not
>>>>determine meaning, neither is it determined by meaning. Buzzword
>>>>bingoish: it is orthogonal to meaning.
>>>No, it is not orthogonal because it can be, and usually is, the carrier
>>>of meaning.
>>[semi-orthogonal ?]

> Semi-pregnant? :-)

Exactly. And semi-closed world, of course.

>>Let's zoom in here:
>>The store/forward structure carries the signs. Can we or can we not
>>change that structure whithout affecting the stored/transported signs?
>>Can we change the signs without affecting the conveyed meaning?

> Not without agreeing first on what the new interpretation is of the
> structures and the signs.

Let's zoom in some more:
Not caring about meaning, we can change structure without affecting the signs:
"The secret agent walked into the room." "The agent walked into the secret room." and we can change both signs and structure, and yet convey the same meaning:
"At 4:05 pm tomorrow the doors will open" "The doors will open tomorrow at 16:05"

>>>I could send a simple string with flat text or I could add structure in
>>>the form of XML mark-up and then send it to you. If we have agreed
>>>before on what this markup means then the added structure will add
>>>additional meaning.
>>??? Are you suggesting we can add meaning without changing the

> Of course we can. Why does that surprise you? If I first send you "Harry,
> 43" and then "<name>Harry</name><shoesize>43</shoesize>" then you will
> probably know more after the second message. Note that no change of
> agreement is necessary.

Are you telling me the second message relates to same Harry and 43 as the the first? It contains some of the signs which are also in the second message. Do they mean the same? Their closeness suggests it. Your use as an example suggests it. If I had to make a decision based on it I'ld say they do.

Not trying to disqualify the use of tags, though. They are very useful. They do help to make data out of signs :-) Received on Mon Aug 23 2004 - 18:19:36 CDT

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