Re: SKOS comment: change of namespace (ISSUE-117)

On Fri, Jul 25, 2008 at 8:00 AM, Alistair Miles <alistair.miles@zoo.ox.ac.uk
> wrote:

>
> The argument against sticking with the old namespace is that the semantics
> have changed significantly. I don't think that's necessarily true. The only
> change to the semantics of an existing element is the change of
> skos:broaderto not being transitive. However, all data I know of currently
> published
> fits perfectly well with the usage pattern that "skos:broader is used to
> assert a direct hierarchical link between two concepts" -- and hence is
> perfectly consistent with the new data model. If anyone can provide a
> counter-example I'd be very grateful.
>

http://lcsh.info/

The Hierarchical Relationship: Broader Topics and Narrower Topics
[...]
A heading is normally linked to one immediately next to it in the subject
heading hierarchy. Since the referenced headings are linked in turn to ther
headings, reference for distant relationships are no longer made. References
leading to two or more levels in a hierarchy reflect an obsolete practice.

Library of Congress Subject Headings (22nd edition) vol. 1, p. x

This policy corresponded to the introduction of explicit BT and NT
relationship designators, and is incrementally implemented. This instruction
is only plausible because the BT relationship is transitive ("No matter what
the level at which one enters the hierarchy, one can follow either the  BT
or NTs to find the broadest or most specific headings" (ibid)

In current LCSH, we have separate, explicit assertions that:

1: Technological innovations BT Inventions        (TI  BT I)
2: Inventions BT Creative ability in technology    (I BT CAIT)
3: Technological  innovations BT Creative ability in technology   (TI BT
CAIT)

Under the tranditional meaning  of BT, assertion 3 is uncessary, due to the
semantics of hierarchical relationships.  Under LC rules, which are semantic
preserving, it is safe to remove this link.

Removing it, we have

TI BT I ,  I BT CAIT   |= TI BT I, I BT CAIT,  TI BT CAIT

Under the original, correct, skos  semantics, broader operates the same
BT.

TI broader I,  I broader CAIT |= TI broader I, I broader CAIT, TI broader
CAIT

Under the new semantics
TI "broader" I, I "broader" CAIT |/= TI broader CAIT

The semantics of the new "broader" are **clearly** *not* the same as BT, or
the correct broader.

IF you want to keep the same namspace, rename the new "broaderTransitive"
relationship to "broader", and rename the new "broader" relationship to
"directllyAssertedBroader".

The BT relationship is intrinsically hiearachical and thus transitive.