13:02
*** Log started on 2000-10-10 UTC-0400 ***
13:02 [RRSAgent]
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13:04 [RalphS]
(log may be some minutes behind from some mirror sites)
13:04 [DanC]
I'm getting "we're sorry, your access code is not recognized" using the code from Eric's message of
13:04 [DanC]
Tue, 10 Oct 2000 08:53:39 -0400
13:05 [DanC]
operator suggests changing 1st digit to 2
13:06 [DanC]
Attendance: Connolly, Swick, Dave Beckett
13:06 [DanC]
Attendance: Steve Newcomb present
13:07 [emiller]
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13:07 [RalphS]
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13:07 [RalphS]
+Eric Miller
13:08 [DanC]
SteveN claims to be in a channel with the same names, but we can't see him.
13:09 [DanC]
expected: brickley
13:09 [DanC]
expected: freese
13:10 [DanC]
attendance: regrets in advance: EMiller probably needs to leave soon
13:10 [emiller]
hi steve?
13:11 [RalphS]
log is http://www.w3.org/2000/10/10-topicmap-rdf
13:11 [DanC]
expected: michel
13:12 [RalphS]
-> http://www.w3.org/2000/09/25-topicmap-rdf previous discussion
13:12 [DanC]
agenda ideas, anyone?
13:13 [RalphS]
+Dan Brickley
13:13 [DanC]
old business: Connolly to invite danbri; DONE.
13:13 [RalphS]
+Art Barstow
13:14 [DanC]
[more old business, not reviewed]
13:14 [DanC]
===== upcoming topicmap stuff
13:14 [DanC]
Steve: we've set a deadline of [?] so we can announce at XML 2000
13:15 [DanC]
SN: I've been asked to chair
13:15 [DanC]
SN: not sure I will, though
13:16 [DanC]
old business: I think this is done: emiller: send announcement to www-rdf-interest
13:16 [DanC]
old business: I think this ACTION is still pending: SteveF: grab some dublin core examples [and do something... not sure what.]
13:17 [DanC]
XML 2000... is that this? [[[
13:17 [DanC]
"Don't miss your chance to join us at XML DevCon
13:17 [DanC]
Fall 2000, November 12-15, 2000, San Jose
13:17 [DanC]
Doubletree Hotel, San Jose, CA. For more
13:17 [DanC]
details, contact Dale Sherman at 212.251.0006
13:17 [DanC]
ext. 12 or at dale@camelot-com.com. "
13:17 [DanC]
"Our New York event sold out."
13:17 [DanC]
"You'll be joined by 4,300+ XML attendees"
13:17 [DanC]
http://www.xmldevcon2000.com/
13:17 [DanC]
]]]
13:18 [emiller]
http://www.gca.org/attend/2000_conferences/XML_2000/default.htm xml 2000 conference?
13:18 [RalphS]
+Michel
13:18 [danbri]
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13:20 [DanC]
ah... emiller is right; Washington DC [date?]
13:20 [DanC]
I note that the word "washington" doesn't occur on ....XML_2000/default.htm
13:20 [DanC]
ah... it does, but as graphics, not text.
13:20 [emiller]
xml 2000: Dec 3-8 Washington DC
13:23 [DanC]
grumble... GCA conference page isn't WAI-happy; no alt text for the most important info on the page: date, city
13:24 [RalphS]
+Eric Freese
13:24 [DanC]
connolly claims keywords/description are widely deployed; emiller disputes this claim.
13:25 [danbri]
emiller accepts action to circulate evidence pro/con this claim to some public archived list.
13:25 [danbri]
emiller?
13:25 [DanC]
old business:
13:25 [DanC]
[12:58] <DanC> ACTION SteveF: grab some dublin core examples [and do something... not sure what.]
13:26 [DanC]
SteveF: ... and see if they could be mapped into topicmap-ese
13:26 [DanC]
SteveF: no progress
13:26 [ArtB]
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13:26 [DanC]
Michel: agenda request: general RDF/topicmap model issues
13:27 [DanC]
====== general RDF/topicmap model issues
13:27 [Anonymous]
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13:27 [Anonymous]
# Appears as XENO.
13:27 [DanC]
Michele: (1) What do we call metadata? seems that for topicmap, there is no distinction. it seems that in RDF there is.
13:28 [danbri]
[[[The distinction
13:28 [danbri]
between "data" and "metadata" is not an absolute one; it is a distinction created primarily by a particular application, and many
13:28 [danbri]
times the same resource will be interpreted in both ways simultaneously.
13:28 [DanC]
Swick: we didn't mean to draw any sharp distinction between metadata and data in the RDF specs. Did we?
13:28 [danbri]
]], from rdf model and syntax intro
13:28 [RalphS]
Ralph: when RDF refers to 'metadata', we mean it in the sense that metadata applications are one use of RDF
13:29 [DanC]
Michel: so (1) is not much of an issue.
13:29 [DanC]
Michel: (2) topicmaps are described as objects, where we describe the data but not the methods. so... nothing about processing.
13:31 [DanC]
connolly: we expect RDF to be processed, but we don't mean to specify any particular processing. This is the same as topicmaps, no?
13:31 [DanC]
Michel: ok... so (2) doesn't seem to be an issue either.
13:31 [danbri]
more context for (2), from rdf schema section 3: [[For example, while an RDF schema can assert that an
13:31 [danbri]
author property is used to indicate resources that are members of the class Person, it does not say whether
13:31 [danbri]
or how an application should act in processing that class information. We expect that different applications will
13:31 [danbri]
use these constraints in different ways
13:31 [danbri]
]]
13:31 [DanC]
Michel: (3) RDF schema is specified as relationships between resources; topicmaps have another layer...
13:32 [danbri]
src for that quote, http://www.w3.org/TR/2000/CR-rdf-schema-20000327/#constraints
13:32 [DanC]
-emiller is excused.
13:34 [danbri]
[discussion of whether 'arcs' and/or 'topics' are --in some sense-- neutral]
13:34 [RalphS]
Steve: "a topic is the thing that gives form to a platonic idea"
13:35 [RalphS]
Michel: can't write a relationship between 2 documents...
13:35 [RalphS]
... must say "document A is represented by topic 1, document B is represented by topic 2, topics 1 and 2 are related."
13:36 [RalphS]
Michel: e.g. in the RDF examples, "author" would be a topic
13:36 [RalphS]
... "subject" would be in the occurrence role and the role would be "description"
13:38 [RalphS]
DanC: earlier it was said that every topicmap could be written as a directed labeled graph...
13:38 [RalphS]
... is the reverse true; every DLG can be interpreted as a topicmap?
13:38 [RalphS]
Steve: yes
13:42 [RalphS]
DanC: the smallest RDF model is empty, but the next-smallest has 2 nodes and 1 arc. What is the smallest topicmap?
13:42 [RalphS]
Eric: 1 topic
13:44 [EFreese]
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13:44 [EFreese]
# Appears as XENO.
13:45 [RalphS]
DanC: smallest is 1 topic with a label?
13:49 [RalphS]
DanC: from RDF's point of view, for example, every GIF image on the Web is a resource
13:49 [RalphS]
Michel, Steve: topicmap wants these to be deliberately stated as 'stand-ins' for topics
13:49 [RalphS]
... may be that there is an extra layer in topicmap that is "notion identification machinery"
13:51 [RalphS]
DanC: in general, [we] think of a URI as playing the role of a noun-phrase in natural language
13:53 [RalphS]
Michel: "degenerate topics" are topics without names [and without semantics]
13:54 [RalphS]
Steve: suppose we took the position that association links, if they don't point to topics...
13:55 [RalphS]
... are regarded as pointing to the "subject identity" of a topic
13:55 [RalphS]
... where "subject identity" is some hunk of information that is regarded by the author of the topicmap as the best possible unambiguous expression of what notion he is thinking about
13:55 [RalphS]
... "subject identities" are the binding points in topicmap land
13:56 [RalphS]
Steve: if multiple topic links point at the same resource saying it is their subject identity, then all those topics are regarded as being one and the same
13:56 [RalphS]
Steve: could relax the [linking] constraint such that everything pointed to is either a topic or is a subject identity
13:57 [RalphS]
DanC: sounds right
13:57 [RalphS]
Michel: could get confusing to implementations to have such choices between two interpretations
13:57 [DanC]
hmm... while that solves some things, it may introduce items from the RDF issues list: "are we pointin got the XML element, or the RDF resource it denotes?"
13:58 [RalphS]
Michel: I understand "topics" as the connecting hub
13:59 [RalphS]
Steve: let's say that an association link is the equivalent of an RDF arc...
13:59 [RalphS]
... if we say that association links are not required to point at topics,
13:59 [DanC]
something I'm noticing... topicmaps seem, like XLink, to be n-ary at heart, whilc RDF is binary at heart. RDF's binariness is kinda painful, to me, lately, so I have an open mind here.
14:00 [RalphS]
Steve: ... but if they do point at topics they work just as before,
14:00 [RalphS]
... however if they don't point at topics then consider what they point at as being subject identities
14:00 [EFreese]
TM are n-ary
14:00 [RalphS]
Michel: doesn't seem implementable
14:00 [danbri]
danc: does the DAML work address the binary/n-ary concern? eg. common strategy for doing n-ary over edge-labelled graphs...?
14:00 [danbri]
(um... that was a question to danc not an attribution!)
14:01 [DanC]
I've run into the binary/n-ary issue in DAML work. I came up with an approach (see restrictedBy etc.). I'd hardly call that a "common strategy" but it's there.
14:01 [RalphS]
[Ralph worries about two meetings here!]
14:04 [RalphS]
Steve: [is it the case that] if you point to a resource that isn't a topic, then that resource doesn't have any occurrences, right?
14:08 [RalphS]
DanC: in RDF identifiers are only necessary to be sure you are talking about the same thing in two different documents
14:08 [RalphS]
... different URIs in different documents *might* be talking about the same thing but we need more smarts to deduce that
14:08 [RalphS]
... the same URI in two different documents is always talking about the same thing
14:09 [RalphS]
DanC: RDF syntax does have a way to talk about things without having a URI for them
14:11 [DanC]
ACTION SteveN: propose to relax that contraint in windam(sp?) and report back. (Michel's reservation noted)
14:11 [DanC]
... back to Michel's list of model differences.
14:12 [RalphS]
Michel: notion of something like RDF Schema ...
14:12 [DanC]
Michel: (4) about RDF schemas... in some ways there's an equivalent, but in some ways there is...
14:12 [RalphS]
... no equivalent idea in topicmap
14:13 [RalphS]
Michel: can define some [similar things] in DTD. see definitions of "housekeeping topics"
14:14 [RalphS]
Michel: topicmap has "topic type", "topic name", ??
14:14 [RalphS]
... value of a link is unconstrained
14:16 [ArtB]
[I couldn't understand the third item in Michel's list but I thought he said "inference rule" ...]
14:18 [RalphS]
EricF: "public subjects" are something like the shared concepts that are defined in an RDF schema
14:20 [RalphS]
Steve: consider "scope"
14:21 [RalphS]
... when we assert an arc; when we say that two things have a relationship
14:21 [RalphS]
... the scope can be "unconstrained"; there is no situation we know of in which the arc is not valid
14:21 [RalphS]
DanC: e.g. "the successor of 2 is 3"
14:21 [RalphS]
Steve: right, though this might be an expression of someone's opinion
14:22 [RalphS]
... however, could be narrow scopes
14:22 [RalphS]
... e.g. "sensible teeth" vs "sensitive teeth". In the French language, only the context distinguishes which meaning of "sensible" is meant.
14:24 [RalphS]
Michel: a topic can have many names
14:24 [danbri]
[aside: (real world) eg. http://xmlns.com/wordnet/1.6/Tooth is one notion of tooth that has a unique web name]
14:24 [RalphS]
... but we know when we are talking about the same topic
14:24 [RalphS]
Michel: to know what thing the name applies to, we filter it using the scope
14:25 [RalphS]
... when we give a name for an association or for a role, we really give a set of names that are represented by a topic
14:25 [RalphS]
Steve: this is separate from addressing
14:26 [RalphS]
Steve: topics have names, which are not their addresses, and they have occurrences
14:26 [RalphS]
... topics play roles with respect to other topics; these are their 3 characteristics
14:26 [RalphS]
... all 3 characteristics have scope
14:27 [RalphS]
... scope is expressed as a set of topics (not topic names)
14:28 [RalphS]
DanC: consider a typical RDF sort of example; "Bill Clinton" and "United States" are related by "is President of"
14:28 [RalphS]
... this will not always be true, but we want to represent the fact that it was true in 1999
14:29 [danbri]
more, er, context for the record. Graham Klyne posted this proposal for representing contexts to the RDF Interest Group: http://lists.w3.org/Archives/Public/www-rdf-interest/2000Sep/0028.html
14:31 [RalphS]
DanC: RDF uses reificiation to represent statements then any statement can have additional arcs. There is no restriction to the arcs that can be added to a statement.
14:32 [RalphS]
Michel: this representational idea might come out of the "conceptual model" subgroup
14:32 [DanC]
my point is that there's a relationship topicmap:scoped-by(?association, ?set-of-topics), and I wonder if topicmap:scoped-by can have subproperties, and whether topicmaps have a slot for them.
14:36 [RalphS]
DanC: different example; "red book is good". Bob believes this statement, Fred refutes it.
14:37 [RalphS]
... in topicmap I expect I can put Bob and Fred into the context of the statement but I don't know how to say Bob believes it and Fred doesn't.
14:38 [RalphS]
DanC: I want to structure this such that it is clear that Bob and Fred disagree.
14:42 [RalphS]
DanBri: can you ascribe probabilities to associations in topicmap?
14:42 [RalphS]
... for example, that Bob gives probability 90% to the statement "book is red"
14:42 [RalphS]
... does this make sense in topicmaps?
14:42 [RalphS]
Steve: people make new topics, e.g. for chronology
14:43 [RalphS]
... could do the same with probability levels
14:46 [RalphS]
Steve: wrt "topicmap only permits positive statements" ...
14:46 [RalphS]
... if you are interested in the fact that an association is absent from a list, this is a 'query'
14:47 [RalphS]
... so if you want to know 'Joe does not believe', you look for the absence in a query
14:47 [DanC]
I think that if I look at topicmap:scoped-by as a subproperty of rdf:type, I can be happy.
14:48 [DanC]
i.e. "scoped by" is a sort of one-place predicate mechanism in topicmaps, and we use rdf:type for one-place predicates.
14:50 [danbri]
ralph: "is there an explicit notion of unknown? can I distinguish between not knowing and false?"
14:53 [RalphS]
Steve: not in general, you need to know something about the semantics of the specific association
14:54 [RalphS]
... in order to know how you might differentiate between "unkown" and explicitly absent
14:57 [danbri]
more context: interesting work bridging the two worlds... http://www.cse.ogi.edu/~shawn/rpe/bowersrpe.pdf
15:03 [DanC]
michel's message http://lists.w3.org/Archives/Public/www-rdf-interest/2000Sep/0194.html
15:05 [DanC]
Michel: we've been able to exploit XLink implementations to deal with one topicmap dataset
15:09 [DanC]
proposed: Mon, 23 Oct [what time?]
15:09 [DanC]
1500Z (11amET)
15:09 [DanC]
ok by me.
15:09 [DanC]
RESOLVED.
15:09 [ArtB]
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15:10 [DanC]
ADJOURN.
15:10
*** Log ended on 2000-10-10 ***