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Re: [SKOS] "Mapping" vs "standard" relationships

From: Alistair Miles <alistair.miles@zoo.ox.ac.uk>
Date: Wed, 21 Jan 2009 11:41:40 +0000
To: Antoine Isaac <aisaac@few.vu.nl>
Cc: Thomas Baker <baker@sub.uni-goettingen.de>, SWD Working Group <public-swd-wg@w3.org>
Message-ID: <20090121114140.GB27719@skiathos>

Hi Antoine,

Just for the record, I'm happy to accept your final judgment on this.

My 2c...

On Tue, Jan 20, 2009 at 11:35:54AM +0100, Antoine Isaac wrote:
>
> Hi Alistair,
>
> I don't see a real opposition here, unless Tom did really intend to discuss evolution and enrichment in the Primer: to me the core of his proposal lies in the paragraph:
>
>>> > The argument could run as follows: Ideally, we should be able
>>> > to tell from provenance information who said what, but in
>>> > practice, Semantic Web data is often merged in simple ways that
>>> > obscure the origins of assertions.  The distinction between
>>> > "mapping" and "standard" relationships is one of etiquette --
>>> > directly asserting "standard" relationships sends the message
>>> > that the asserter considers herself qualified to define the
>>> > relationship in a standard way.  For everyone else, the polite
>>> > thing is to assert a "mapping" relationship.

Well, I don't like the idea that "mapping" vs. "standard"
relationships should carry any connotation such as "the asserter
consider herself qualified...". This was not what I had in mind at any
stage of the design process.

Generally, I think it is a bad idea for properties to carry any
connotation regarding authority or provenance. This includes a
connotation such as "...the asserter considers herself
qualified...". I discussed this in an email I wrote back in Feb last
year [1] (see section "My Position").

>
> which I agree with, even though the appropriate wording for the Primer might be difficult for me to find :-/
>
> Such a paragraph is I think rather agnostic towards promoting KOS evolution and enrichment as full-fledge scenarios. Note that like you, I would be actually uncomfortable with extensively discussing KOS evolution and enrichment in the Primer.
> As a matter of fact, the only mention of these in the Primer is:
>
>> However, the use of mapping properties might also be appropriate in cases where someone other than its owner needs to enrich the semantic relationships within a particular concept scheme.
>
> Do you think that sentence is too strong? For me it's a relatively open sentence, in line with what you propose -- it is not *discussing* the scenario. IMHO, doing more than using this "might" (even if to say explicitly that this is an open scenario) could actually puzzle the reader by giving more importance to these potential "cases" than what is required.

I don't have a problem with that sentence, but see also below.

>
> So my concrete proposal would be:
>
> 1. Replace the last two sentences of [[
>> By convention, mapping properties are used to represent links that have the same intended meaning as the "standard" semantic properties, but with a different application scope. One might say that mapping relationships are less inherent to the meaning of the concepts they involve. From the point of view of the original designer of a mapped KOS, they might even sometimes be wrong.
> ]]
> by something that would follow Tom's line in the abovementioned paragraph, and nothing more.
>
> 2. Keep the following paragraph:
> [[
>> Mapping properties are expected to be useful in specific applications that use multiple, conceptually overlapping KOSs. By convention, mapping relationships are expected to be asserted between concepts that belong to different concept schemes. However, the use of mapping properties might also be appropriate in cases where someone other than its owner needs to enrich the semantic relationships within a particular concept scheme.
> ]]
> as such.
>
> Is that compatible with your position? 

Well, I don't agree with Tom's line, so I guess not. 

How about something like...

""" The SKOS mapping properties skos:broadMatch, skos:narrowMatch and
skos:relatedMatch are used to represent links that have the same
intended meaning as the semantic relation properties skos:broader,
skos:narrower and skos:related. However, by convention, mapping
relationships are only asserted between concepts that belong to
different concept schemes. """

I actually think this is all the Primer needs to say. 

If you wanted to provide some additional context, you might add
something like...

""" Mapping properties are expected to be useful in applications that
use multiple, conceptually overlapping KOSs; for example where an
application is providing integrated search across bibliographic
metadata from several different sources, each of which has used a
different KOS to index items. """

If you really wanted to go into more detail about the SKOS data model
for mapping properties, you could say something like...

""" Advanced SKOS users may note, however, that there are no formal
constraints in the SKOS data model restricting the use of SKOS mapping
properties to link only concepts in different schemes. For further
discussion see section 10.6.1 of the SKOS Reference. """

Cheers,

Alistair

[1] http://lists.w3.org/Archives/Public/public-swd-wg/2008Feb/0095.html

-- 
Alistair Miles
Senior Computing Officer
Image Bioinformatics Research Group
Department of Zoology
The Tinbergen Building
University of Oxford
South Parks Road
Oxford
OX1 3PS
United Kingdom
Web: http://purl.org/net/aliman
Email: alistair.miles@zoo.ox.ac.uk
Tel: +44 (0)1865 281993
Received on Wednesday, 21 January 2009 11:42:18 GMT

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