facets (RE: [sc34wg3] Association items)

Nikita Ogievetsky sc34wg3@isotopicmaps.org
Mon, 13 Jun 2005 23:55:59 -0400

! | To me facets where meant to indicate properties like age, weight,
! | height, etc. (monadic predicates indeed).
! Yes, but they were restricted to representing properties of
! information resources. Also, the value of the property was restricted
! to being a topic. Like you wrote they are very similar to occurrences,
! but run the other way. Occurrences let you say that resource X is
! relevant to topic Y, while facets let you express that resource X is
! written in language Z. In one sense they could be described as working
! in opposite directions, occurrences topic -> resource and facets
! resource -> topic.
Hmmm... I am not a big specialist in HyTime and facets. What you say is
perhaps correct. However, back five years ago I was using facets in the
following way (upon consulting with people who knew...):

<facet type="search-order">
	<fvalue type="shape" href="leading-circle" facetval="0"/>
	<fvalue type="usage" href="dingbat" facetval="1"/>
	<fvalue type="elements" href="flower" facetval="2"/>

Where "type" and "href" attributes are pointing to topics, and facetval
attribute represents the order number (which I was dynamically changing,
thus reordering tree-projection of the topic map).
Was it an inappropriate usage? I would appreciate if one of the editors of
HyTime Topic Maps or somebody else could comment.

! | Now most people use occurrences for this (as far as I know - not
! | associations as you and Murray suggest - please correct me if I am
! | wrong).
! For the examples you gave one would use occurrences, true.
! | Use of occurrences for this purpose is quite weird, because
! | occurrences were originally meant to represent relationships between
! | topics and resources (occurrence of a topic in a resource).
! Well, a string is also an information resource; it just happens to be
! stored inside the topic map instead of outside.

Yes, but agree that number "1" is a weird resource for a topic "dingbat" to
be occurred in. However, it is easy to find some justification for it. 
Note that I am not disagreeing (in the end I was one of the first to be
growled at for using occurrences in this matter), but rather pointing out
the old issue.