-
DRAFT -
RIF Telecon 4 Sept 07
4
Sep 2007
See
also: IRC log
Attendees
Present
csma, Dave_Reynolds, AllenGinsberg, josb, LeoraMorgenstern, Harold, +43.512.507.9aaaa, Stella_Mitchell,
ChrisW, barry_b, PaulVincent, DougL, Sandro, Gary_Hallmark, DavidHirtle, luis_polo, Hassan_Ait-Kaci, Michael_Kifer, DaveReynolds
Regrets
IgorMozetic, AxelPolleres (unstable connection,
unlikely that I can dial in), PaulaLaviniaPatranjan
(unstable connection, unlikely that I can dial in)
Chair
Christian de Sainte-Marie
Scribe
Allen Ginsberg
Contents
<ChrisW> Scribe: Allen
Ginsberg
<ChrisW> scribenick:
AllenGinsberg
<csma> Chair: Christian de
Sainte Marie
<csma> Scribe: Allen Ginsberg
<csma> scribenick:
AllenGinsberg
Admin
csma: action
review
chrisW: action 334
closed, 335 done
minutes accepted for aug 28 telecon
Liason
csma: no action
to review
<PaulVincent> OMG PRR: no news
F2F
csma: everyone
please fill out f2f survey
<sandro>
F2F7
Register/Regrets
chrisW: no unpdates on f2f
csma: first draft
agenda by end of next week
... skipping UCR item because Axel not here
... any volunteer to review another one?
<Harold> As I mentioned, Axel and Paula told me they
have only a shakey connection from the Reasoning Web
Summer School in
chrisW: any
volunteers for next week?
csma: Axel should
do it next week
<ChrisW> http://www.w3.org/2005/rules/wg/wiki/D._Evaluation%3A_Use_Cases
chrisW: dave you did use case 8?
dave: stuff has
changed
<ChrisW> http://www.w3.org/2005/rules/wg/wiki/UC8_Worked_Example
dave: can do UC 8
next week
AllenG: can do UC3 following week
csma: move on to BLD
UCR
BLD - RDF
csma: action
review
... sandro action 336?
sandro: continued
csma: 337?
harold: continued
csma: 338
chrisW: 338 is done
(by Gary)
<Harold> New actions come in for me, too, with the
discussion and work Sandro started for the successor to asn06.
<ChrisW> Harold, do you want
to record some actions?
csma: jos to discuss changes to RDF compatibility section
<josb>
http://www.w3.org/2005/rules/wg/wiki/Core/RIF-RDF_Compatibility
<Harold> No, that's an 'informal' action.
jos: cleaned it
up....make more readable and to incorporate new items and resolutions
... also included new comments and discussion itmes
... biggest thing, found more elegant way to define the semantics, so now
easier to read etc
csma: does anyone
have clarification qustions?
chrisW: I have
one...in common interpretations section condition 2
... what is condition 2 doing?
jos: just makes
sure that whenever you use an element as a property then it is in the set Ip
AllenG: (technical
discussion of condition 2)
chrisW: just says
all slots are RDF properties?
jos: yes
... Michael had some skepticism concerning the semnatics?
... especially concerning the combination semantics; I responded in email
mkifer: I didn't
get a chance to read it yet.
jos: let's
continue in email
csma: did you (Jos) mean that an RDF graph can be translated into RIF
rules?
jos: yes.
... actually translated to facts
csma: that means rif includes rdf?
jos: no...it
means that if you want to use RDF with RIF you are implictly
assuming this semantics
csma: does it
mean that any RDF can be expressed as a RIF rule set?
jos: any kind of
rdf entailment maps into entailment in rif
mkifer: this is the
problem: the combined semantics isn't needed because rif
already allows for that embdding
<josb>
http://lists.w3.org/Archives/Public/public-rif-wg/2007Sep/0001.html
jos: let's
continue that over email
mkifer: ok
csma: let;'s go over other issues in the email one-by-one
jos: 3 issues
related to identifiers...
... absolute iri's versus rdf
use of uri references
... might need a conversion?
dave: rdf uses "rdf uri references"
... they were trying to hone in on iri's before the irs spec was finalized
... i suggest we just leave it as iri's
<sandro> DaveReynolds:
What the RDF spec uses is "RDF URI References" which is a confusing
term. It's not "URI References". It was, rather, their best attempt
to anticipate what IRIs would be. There may be a
difference around spaces. I suggest we not dwell on any differences.
jos: I was
confused by different statements in the specs
<sandro> Jos:
I was trying to figure out if we need to take into account the conversions
between URIs and IRIs.
dave: we don't
need to worry about conversion
<sandro> DaveReynolds:
I don't think we do. We just treat them as IRIs.
<sandro> +1 (just treat them
as IRIs)
dave: in the iri specs conversion algorithms would be defined
... we certainly wouldn't define new conversions ourselves
csma: dave we are missing some of your audio....
<DaveReynolds> yes
csma: so the
solution is to use absoluete iris
chrisW: do we need
to refer to uris at all?
<DaveReynolds> exactly, don't
point to any conversion, just talk about IRIs
jos: for the
sake of rdf compatibility
sandro: rdf uri references are not uris
<josb>
http://www.w3.org/TR/rdf-concepts/#section-Graph-URIref
chrisW: they were iri's before iri's were defined
sandro: I agree we dave that we don't need to worry about these issues
... we are basically tracking an evolving standard
<DaveReynolds> I proposed a
form of words (derived from the SPARQL spec) before,
I can find that again
sandro: just talk
about iri's and maybe include a note to deal with
special cases
jos: investigate
further?
sandro: not us.
csma: do we need
a formal decision?
... any objections to just talking about iri's?
none
<sandro> Sandro: The issue
that I think is real is what we say you do about the odd little corner cases
like an RDF URI Reference that is not an IRI -- eg one with a space in it.... I suggest we ignore this
issue. (I think concurring with Dave on this suggestion)
jos: 2nd issue:
some rdf literals are not strings accroding
to xml schema strings
... but we didn't decide whether we want to go with xmls
1.0 or 1.1
<Harold> We certainly should be prepared for 1.1 and
for now encourage RIF users to stay in the common subset.
jos: not clear
about all the consequences of doing one or the other
chrisW: can we
leave these decision to implementors of rif?
csma: do you mean
in rif instance docs?
jos: yes we
could, but then we should say something about rdf
literals that are not xml 1.0 strings
chrisW: what does xmls 1.0 say?
<sandro> Jos:
we need to say what to do if you see an xml 1.0 literal string
jos: doesn;t say anything
dave: we should
leave the value space unconstrained (as in xmls 1.1)
... that doesn't stop people from using 1.0 libraries to process stuff
... in the spec we need to point to a specific spec
... 1.1 isn't at spec yet.
csma: but we
never investigated the consequenses of using 1.1 as
reference for xml types
dave:
agreed...there may be other issues, e.g., builtins
csma: somebody to
take an action with regard to xml datatypes included
in rif
... volunteers/
... we need someone with good xml expertise
... gary?
gary: haven't
been tracking 1.0 vs 1.1
<ChrisW> important point jos made, we can't just leave this up to implementors because we agreed to include XML datatypes directly as part of RIF syntax
dave: what about
asking the xml schema group?
csma: yes
<DaveReynolds> not me
jos: i can
... but they haven't responded to earlier email yet
sandro: sending a
comment to working group would be good
... i can try talking to the people directly, or send
a message to working group
csma: actions?
<ChrisW>
ACTION: debruij to send message to XML Schema WG comments list
[recorded in http://www.w3.org/2007/09/04-rif-minutes.html#action01]
<rifbot> Sorry, couldn't find
user - debruij
action taken by jos to send comment to xml schema
working group
<ChrisW>
ACTION: jdebruij to send message to XML Schema WG comments list
[recorded in http://www.w3.org/2007/09/04-rif-minutes.html#action02]
<rifbot> Created ACTION-339 -
Send message to XML Schema WG comments list [on Jos
de Bruijn - due 2007-09-11].
jos: ill-typed
literals in rif vs rdf
... treatment is different
<josb>
http://www.w3.org/2005/rif/rdf-ill-typed-literal/uri-encode("s"^^u)
jos: I made a
suggestion (see link in irc)
... map ill-typed literals to uris. Is this a good
idea?
<sandro> rifbot,
status
csma: don't
ill-typed literals in rules make them uninterpretable
and therfore who cares?
jos: they can
occur in rdf data, so we need a way to treat them in rif
csma: ah this is
for the combination semantics?
dave: this seems
to be an unimportant case. in actual data you don't let ill-typed literals
through. this isn't practically important
... just say the embedding only works for well-typed case
csma: basically
agree with dave
jos: i don't agree. why not support all of rdf?
csma: it doesn't
mean that rif rules can't interact with all of rdf data, it only means that some rdf
data can't be translated into rif rues
<Harold> Jos' proposal re
ill-typed literals could still come into RIF: where we deal with exceptions,
partial compliance, etc., anyway.
<Harold> (see Sandro's
earlier wiki page)
jos: but this
comes into play with queries - rif query over rdf-data (containing ill-typed literals)
csma: but if rdf knows what to do with them, then rdf
can deal with them
jos: reiterates
point about query-answering
chrisW: something
that understands rdf can do the translation for rif vs. rif itself knows what to
do
... how complicated is this? if uncomplicated we can handle all of rdf
csma: but at what
cost?
jos: only
implementations that care about rdf would be affected
csma: but this
contradicts your combination semantics argument,
... when you try to embed the rdf graph as rif rules you would get a syntax erro
(with ill-typed literals)
chrisW: in support
of csma's argument:
<sandro> Jos:
I DONT propose we support ill-typed literals, instead
I propose we translate to URIs.
jos: rif doesn't need to support ill-typed literals, we are
translating to uri's
chrisw: so you are
really in agreement (with csma)
<josb>
http://www.w3.org/2005/rif/rdf-ill-typed-literal/uri-encode("s"^^u)
sandro: what do the
uri's look like?
jos: shows link
in irc
csma: ok
<MichaelKifer> should the
data type name be part of such a uri?
jos: does this
comply with best practices?
sandro: this is a
pretty weird thing to do (but legal, i think)
... it;s a weird hack, but might be our best option
csma: any
objections to doing this?
mkifer: basically a
good idea, but need to work on details, e.g., other languages might want to use
this mechanism
sandro: why did rdf do this? probably because it would be impossible to
decide whether the literal is really ill-typed
csma: so we table
this issue for now?
sandro: jos can you edit the page to show an actual example/
jos: yes
<josb>
http://lists.w3.org/Archives/Public/public-rif-wg/2007Sep/0013.html
jos: there are 4
additional issues (see link in irc)
csma: once we
resolve all these issues are we done with compability?
jos: it
depends...doc would still need examples, etc. There are other related issues,
but we are pretty close
csma: do we need
to raise those other issues formally?
... yes
<ChrisW>
ACTION: chris to investigate raising Jos' identified issues [recorded in http://www.w3.org/2007/09/04-rif-minutes.html#action03]
<rifbot> Created ACTION-340 -
Investigate raising Jos\' identified issues [on Chris
Menzel - due 2007-09-11].
csma: chris will you ask deborah to
create those seven issues?
chrisW: ok
... sandro can you remove chris
menzel from the list?
sandro: yes
<ChrisW>
ACTION: cwelty to investigate raising Jos'
identified issues [recorded in http://www.w3.org/2007/09/04-rif-minutes.html#action04]
<rifbot> Created ACTION-341 -
Investigate raising Jos\' identified issues [on
Christopher Welty - due 2007-09-11].
<ChrisW> zakim
close item 5
Arch
- Data Models
csma: action
review
action 331 continued
action 330 done
csma: action 258
done?
dave: yes a long
time ago
... we discussed 258 at the last f2f.
csma: action 258
closed
action 256 continued
<scribe>
ACTION: 254 to
semantics section for arch doc [recorded in http://www.w3.org/2007/09/04-rif-minutes.html#action05]
mkifer: at least
telecon i mentioned splitting the arch doc into two.
csma: let's
obsolete this action for now
action 254 closed
<DaveReynolds> http://www.w3.org/2005/rules/wg/wiki/Arch/Data_Sets
csma: dave do you want to discuss your changes
dave: see link in
irc.
... this is a result of discussion at last f2f.
... there are now 3 subsections relating to differnt isues teased out
... how to identify the data set used by rules
... basically convey the metadata to give an identifier for data set
... 2nd section: data model identification
... how do yo tell the rule process what data model
is being used?
... at f2f we agreed on supporting 3 data models
... i updated metadata vocabulary to accomodate those three
... 3rd section data-model usage: see email discussion about this
csma: so let;s use remaining time to how to embed metadata in rif
jos: there is no
mechanism for specifying meta data in rif
... it's straigtforward to do it, but we need to
decide what we want to include
csma: all we have
is the proposal to use rdf to express metadata
dave: right.
Allen: I missed some of
this...
<Harold> Dave, the current syntax proposal is in http://www.w3.org/2005/rules/wg/wiki/Core.
sandro: the
question is related to extensibility.
... if extensibility is easy then we can let people write their own metadata
schema
<ChrisW> who is cgi-irc?
csma: we need to
get a better feeling of what kind of metadata would be required
<cgi-irc> apparently me for
some reason... strange
<cgi-irc> Doug L
csma: if we only
a small set of metadata maybe we can just get away with afew
attributes and values
chrisW: this is orgthogonal to whther metadata is
done in rdf
<ChrisW> -1 to extenc
<DaveReynolds> don't mind
<Hassan> -1 to extend
<sandro> adjourn
meeting adjourned
<DaveReynolds> bye
Summary of Action Items
[NEW] ACTION: 254 to semantics section for
arch doc [recorded in http://www.w3.org/2007/09/04-rif-minutes.html#action05]
[NEW] ACTION: chris
to investigate raising Jos' identified issues
[recorded in http://www.w3.org/2007/09/04-rif-minutes.html#action03]
[NEW] ACTION: cwelty
to investigate raising Jos' identified issues
[recorded in http://www.w3.org/2007/09/04-rif-minutes.html#action04]
[NEW] ACTION: debruij
to send message to XML Schema WG comments list [recorded in http://www.w3.org/2007/09/04-rif-minutes.html#action01]
[NEW] ACTION: jdebruij
to send message to XML Schema WG comments list [recorded in http://www.w3.org/2007/09/04-rif-minutes.html#action02]
[End of minutes]
$Date: 2007/09/04 16:31:40 $