W3C

- DRAFT -

RIF F2F2, day 2

28 Feb 2006

See also: IRC log

Attendees

Present
see day 1
Chair
Chris Welty, Christian de Sainte Marie
Scribes
Jeff Pan, Peter Patel-Schneider, Jos De Roo, John Hall, Mala Mehrotra, Markus Kroetzsch

Contents


 8:30-10:00 Review Use Cases III

(chair: Chris Welty; Scribe: Jeff Pan, Peter Patel-Schneider)

csma: Mar 8 will be the new deadline of the UCR document then WG review and we will vote on 14 Mar
...just the UC section
...questions?
...Now get to the use cases ...

Third Party Rule-Interchange Services

Chris:Marla's comment is the same
...Any discussion of the use case?

csma:
some concern similar to the 2.5 Human-oriented Business Rules

Allen: it could be, but this is natural use case for
...but I am not sure it is similar
...any device can have mistake, ... I don't know whether we should label it as compliant

csma: then seems that they are different use cases

Allen: it is a very broad area and RIF will be very useful

Chris: any more comments?

UC is approved

Rich Knowledge Representation

Chris: marla has the same comment?

OK

discussion ...

Sandro: I don't understand the section, I see only OWL ++

csma: My understanding is it is not only extension of OWL ...
...the point is the rules are needed to be part of the vocabulary

Paul: are there any existing rule extension of OWL?

Chris: there are

csma: I used OWL as a justification

Francois: My suggestion is to make the RIF language extremely expressive

csma: does it make sense to put the uncle example with the brain one

Christin: the brain one is a real example and the uncle one is not

Sandro: I think we need a real one

Gavin: we need some text to show the connection between OWL and RIF

<scribe> ACTION: Francois to contact Ian about the change of the use case [recorded in http://www.w3.org/2006/02/28-rif-minutes.html#action01]

Chris: Michael, can you explain your comments?

Michael: I think the big picture of the section is fine but we should make it simple for readers to read

Chris: do you have any specific comments on change?

<scribe> ACTION: Michael to provide some specific comments of 2.8 [recorded in http://www.w3.org/2006/02/28-rif-minutes.html#action02]

Michael: maybe we should extend the use case and make it more general

Sandro: ...

Chris: [summarise what Sandro said] We should change the name, existence of OWL is a justification of the need of exchange ontologies
...Proposed new name: Interchanging extended ontologies because there are no standard to cover that

Francois: it seems too technical and I would like to see the applicataion in the title

A main title about the application field, and a technical sub-title

Sandro: sounds like a good idea

Christine: I think the application title is too narrow, what about "compatability between ontologies and rules"
...this is required by many use cases in many different field

Sandro: OK I see the point

Sandro propose: Interchaning rule extensions to ontology languages

Chris: do we need to consider languages outside W3C standards?
...any languages?

csma: topic map

pfps: CYC-L

csma: common logic too, although it is not an ontology language and more like a rule language

Sandro: what aout "Interchaning rule extensions to RDF and OWL"

Don: What about mismatches between source and target systems?

Chris: That is a different use case.
...Title: Interchanging Rule Extensions to OWL (for Brain Anatomy Research)
...
Rationale: That is the use case.

?: Does this cover RDF?

Chris: No, should it be covered?

Jeremy: No, this use case is adequate (for HP).

?: This loses the idea of rich ontology languages.

Chris: This would be a new use case.

Michael: Leave the qualifier off the title, to allow for other examples.

Francois: The qualifier is a good title - it says it all.
...Titles need to be concrete.

Chris: Objections to the title?

Giorgos Stamou: The use is general, the example is just illustrative.

Chris: Title options 1/ no clause 2/ "for" clause 3/ subtitle
...Title: Interchanging Rule Extensions to OWL - A Brain Anatomy Research Example
...Actions 1/ remove uncle example and replace with brain anatomy example
...2/ make title be Interchanging rule extensions to OWL

ACTION on PFPS - ask Ian to make changes to use case

Chris and Michael: modify Michael's action to think about new, related use case

Information Integration

Sandro: Right thing is to have Frank revise to address concerns

?: Perhaps the right thing is to have 2 use cases

Christian:
New topic is "process and supply chain"

?:
Perhaps might integrate remaining part of 2.6

Sandro:
New title is "access to business rules of supply chain partners"

Frank:
2.6 example is FOAF-style rules about telephone contact rules

Christian:
Proposal 1: remaining part of 2.6 fits into 2.1, so 2.6 is deleted
...Proposal 2: remove data integration from 2.1, retitle, and revise, ensuring that there are rules there
...Proposal 3: add new use case about data integration

Sandro:
moving 2.6 to 2.1 doesn't make sense

Christian:
ok

Chris:
objections to Proposal 2?

ACTION on Frank - effect Proposal 2 above

Chris: discussion on Proposal 3

Sandro:
I can take the stuff from the charter and make it into use case 2.9
...Title: Vocabulary mapping for data integration

Christian:
consult with Dave Reynolds

Sergio:
there should be something about incomplete information in the use case

Jeremy:
data integration use case is interesting to HP because it is simple

Hassan:
why is the use case related to incomplete information?

Sergio:
there is often some sort of incomplete information in data integration

Sandro:
This is a synthetic use case - does anyone have a real use case?

Frank:
yes, there should be lots - Fujitsu has done this

Jeremy:
let's do something that can be done fast, let's not try to perfect the use case now

?:
production systems actually don't work on vocabulary mapping they work, as well, on data mapping

Chris:
Sandro will do the use case, Sergio to provide input

ACTION on Sandro - effect Proposal 3 as modified


Chris:
discussion on Proposal 1

?:
there is still something left in the area - something like distributed rule bases

Harold:
the use cases in 2.6 need homes

Christian:
FOAF use case ends up in 2.1

Sandro:
don't see anything valuable left in 2.6

Chris:
objections?

ACTION on Allen as editor of UCR - remove 2.6


Hassan:
status of Use Case titles in ToC

Chris:
proposal is to do this somehow

Hassan:
as long as it works out

Ruleset integration for Medical Decision Support

Chris: Status?

Christian:
change title to above, drop e-learning, concentrate on prescription part (and extend slightly)

Chris:
Objections?

ACTION on Chris: tell Leora to make changes

Break (until 10:40)

Conclusion on Use Cases

(Chair: Christian de Sainte Marie; Scribes: Jos De Roo, John Hall)

<Scribe> ACTION: JeffPan propose extension to prescription example [recorded in http://www.w3.org/2006/02/28-rif-minutes.html#action03]


discusssing UCR/Interchange of Human-oriented Business Rules
merging with 2.6 is not an option

ChrisW:
use case is not close as it stands, needs catching better the intention
...propose to move it for next WD round?

FrancoisB:
have something about BR in first draft is crucial

CSMA:
propose to keep title in first WD
...alternatively Donald to come up with new text by monday?
...text can be removed

RESOLVED no objection


<Scribe> ACTION: JohnHall come up with new text by Monday [recorded in http://www.w3.org/2006/02/28-rif-minutes.html#action04]


proposed title: tools for managing policies and practices in organizations
(discussing a proposed title..)

RESOLVED: new title "Managing inter-organizational business policies and practices"


<Scribe> ACTION: JohnHall to reflect that title in the new proposed text [recorded in http://www.w3.org/2006/02/28-rif-minutes.html#action05]


DONE with UCR discussion!!! fireworks

Next F2Fs

F2F3

Axel: proposal to colocate with next ESWC Montenegro June 11-14
.. either 8-9 or 9-10 is proposed

Igor: afterconference is not an option
...8-9 was originally planned for RIF
...15-16 June not possible

ChrisW: No clash with KR meeting 2-5June

no objection to have next F2F Montenegro either June 8-9 or June 9-10

RESOLVED: to have next F2F Montenegro either June 8-9 or June 9-10

RESOLVED: to have WBS vote per organization

<Scribe> ACTION: Sandro to organize such WBS vote [recorded in http://www.w3.org/2006/02/28-rif-minutes.html#action06]

by next tcon have resolution on the date

<Scribe> ACTION: AxelP to set up logistics F2F page [recorded in http://www.w3.org/2006/02/28-rif-minutes.html#action07]


Peter P-S: Chairs should not impose changes on face-to-face proposals.

Chris
: Chairs have the right to veto dates when they cannot attend

Peter
P-S
: If this is the reason for refusing dates, it needs to made clear. Dates were requested for late June - these dates are not.

F2F4

Christian: The following face-to-face should be mid September - mid November:...Submit proposals asap...Decision at next face-to-face (Montenegro)

Peter P-S: Pre ISWC, Athens (Georgia, not Greece), November. Peter is holding space

Action on Peter P-S: make proposal on Wiki for ISWC, Athens, Nov 2006

Roadmap

Presentation by HaroldB   (slides)

Frank: Production Rules semantics are not monotonic. PR is not true subset in phase 1 - cannot characterize PR with assert and ignore retract. If PR is split from phase II, will have to undo assert - have to retract part of phase 1

 (discussion about semantics of production rules)

<Scribe> ACTION: Frank to make his point on the mailing list [recorded in http://www.w3.org/2006/02/28-rif-minutes.html#action08]

Francois: need for complex 'actions' in production rules (besides complex events and complex conditions)

<Harold> Harold: can already do the syntactic extensions in Phase1

 .. to make clear what might be done semantically in Phase2

<GaryHallmark> +1 on including production rules earlier

<Scribe> ACTION: Harold to explain technically the basis for interoperation between PR and Horn rules [recorded in http://www.w3.org/2006/02/28-rif-minutes.html#action09]


Uli: What are the proposals?

Harold: Show the basis for interoperation between PR and Horn rules item 2 (slide 5), and item 9.2 (slide 13)
 
Uli: 2 or 3 formalisms for phase 2?

Christian: Maybe 9 can then be moved to Phase 2

Uli: What are Phase 1 semantics?

MichaelK:Phase1 is one semantics i.e. FOL entailment (is in response to Uli's question)
...In the roadmap Phase 1 and Phase 2 are unreasonable for 1 year. They need to be divided into packages.

Christian
: Phase 1 is time limited. What does not fit in is by definition not in Phase 1.

Francois
: The semantics discussed are about representation, not process. Declarative constraints can be transformed into reactive rule. It is important to separate representation from process.

Christian
: Discuss this during afternoon.
 ...collect & discuss requirements:
... New Wiki pages for requirements & design goals
...Name and short description, annotate existing requirements where possible
...Refer to existing
...Cut off in 3 weeks

Jos de Roo: Distinguish requirements and objectives

Action on Christian:
create new Wiki page for requirements CSMA: will set up new page for requirements

Lunch break (until 14:00)

Requirements Brainstorming Session

(Chair: Chris Welty; Scribe: Mala Mehrotra)
(see also Sandro's notes)

Paula: Paula's work on list of requirements
...Her work on consolidation of requirements was presented.
...On the wiki list all requirements  & duplicate elimination exists
...on the Wiki that she put up with the classifications.

Sandro
: Had not seen the page – needs time with it

Csma
: Should start from a blank Design Goals and Rqmts page and add to it. Easier for people to compare and add rather than other way.

Chris
: approves

Paul
: Makes sense for us to start from the list of languages that are source and targets
...gives a context or framework that concerns us.

Sandro
: Process is not clear for doing this. Cannot completely interchange ever
...some intersection will be there in RIF which we will have to accept

Chris
: A list of rule languages on wiki is there

Csma
: Choose a pair of real-world rule language that can interchange through RIF . Has to be an implemented language

Frank
: For web services page we had a methodology
...Use the methodology
...identify critical success criteria for goals
Allen: Target set of languages in RIF
... any well-formed rules in the language should have an equivalent representation in RIF – should be the starting point.

Chris
: Wiki page lists 20 systems 8 of which are commercial.

Paul
: Do nott list RL. prioritize the rqmts. Particular class to class. From one PR to another. Straightforward case.

Allen
: Target language to RIF and from RIF to target

Frank
: Precision of semantics
... should be extremely clear what has been translated

Sandro
: Formal semantics – it must be clear what ground facts are entailed by the translation

Paul
: Performance of exchange – real-time requirements

Csma
: Cannot put requirement on the network

Paul
: Design of RIF is simple enough to support high-speed processing
...pragmatic requirement

CSMA
: form of consistency- syntactically and semantic validity

Paula
: support for different kinds of rules

Mala
: Support for meta-data that could facilitate interchange

Deepa
: Tagging the family of rule languages

Gary
: Support for XML facts typed by an XML Schema
...XML document or notes is a collection of facts

Paul
: Content of document – as a business object model. Customer info maintained in an XML document becomes a collection of facts.

Peter
: raises objection; Data vs facts as XML documents

Allen
: Codification of the procedural requirements should be in the RIF. Facts about this.

Paul
: Tag the rule-set

Allen
: Tagging for humans

Paul
: Container for the rules

CSMA
: Rule-set should be the base unit for RIF

Hassan
: Encode rules or rule-sets?

Chris
: What is an example?

Allen:
PR - one is more specialized. Rule prioritization

Hassan
: Two closed systems Priorities, disambiguation of rules

Paul
: RETE vs procedural execution, exclusive rules. Sequential

Francois
: conflict resolution packages can be specified. One is machine-processable. Forward backward chaining, name the specificity of the procedural semantics
...design a way of implementing it
...last one is design of programming language
...out of scope.

Jos de Roo:
Predicates should adhere to No unique names assumption. Open world assumption

Allen
: Two rule sets can be merged into the target ruleset.

Frank
: Maintenance of provenance of the rule
...Ability to work with multiple rulesets with distinct owners
... scoping of rules?
...Separately maintaining traceabilty of the rulesets

Andreas
: provenance wrt rule-sets
...Referencing the provenance while execution

Chris
: Container - circumscribing a set of rules.

Frank
: Not provenance. Scope is needed.

Mala
: Context

Frank
: identified set
...Relationship between sets

Chris
: Needs to be clarified further

Allen
: Translation should be Sound and complete.

CSma
: One pair of language?

Allen
: Only input into the RIF semantics should be same

Csma
; Equivalent rule from and to translation process.
...Ruleset-A -> RIF -> Ruleset B

Hassan
: Same as semantics of the rules should be maintained.

Frank
: Soundness preserving and completeness preserving.

Csma
: Language is sound

Peter and Sandro:
Soundness is not a property of languages

Harold
: Interoperation??

Hassan
: Agrees with soundness not comp.

Harold
: Explains it. Change source to target

Christine
: Language which allows an existential in the head of rules.

Donald
: Adopting a back-based editor to build the rules according to rule structures.

Chris
: XMLSchema?

Donald
: We build rules on top of a fact base and interchange upon a fact model.

Harold
: External data base?

Donald
: Concepts and facts in RIF? If they are part of RIF ok. If they are not

Frank
: Cannot stop it

Paula
: Priorities and preferences

Chris
: Duplication

Igor
: Is this the fourth page on requirements list? What is the point?

CSMA
: This is an opportunity to discuss them alive

Chris
: Important ones surface up.

Harold
: RIF should allow both ends of dimensions: Do not know vs. do not care  - non-determined. Discard can go on during execution. Production rules should have these semantic attributes.

Sandro
: When you translate a rule set in and back out of RIF
...if the systems support similar semantics then you will get them
...square in a round holes.

Sandro:
Can have same syntax for production rule - ?

Alex
: Define a core and have a set of features that rules set can support. What is the semantic of the interoperation makes most sense. 

Csma
: You should know what your translator does.

Jos de Bruin:
Features compatibiloity

Allen
: garbage in garbage out

Csma
: graceful failure? If RIF translator is not compliant then it should not just fail.
...Describe behavior.

Chris
: RIF should represent the mapping accurately.

Frank
: Inverse rule translations
...get back same ruleset. Round-trip preserving.

Michael
: It is your job.

Allen
: Agrees.

Michael
: Make sense of this list of reqmt.

Gary
: Procedural attachments can be defined using arithmetic such as, older than for eg. should be able to translated in RIF

Chris
: A programming language for RIF.

Gary
: A language where functions can be expressed. Esp. Boolean operators. Use the function in the rule
...and the translation could move this along during the translations.

Chris
: Want functions.

Donald
: Logic should be there

Chris,
Gary : Naming a rule.

Harold
: Can ask the age of the first born; Is greater than some other function.

Paul
: Business logic cannot be expressed as a rule. Support rules. Condition and action rules. Rule with no head.

Harold
: Business meaning is preserved in the interchange.

Peter
: Telepathy

Chris
: If the fact base on which you are building the rules
... the semantics should be preserved. No comments are needed.

Allen
: RIF has to input statements in OWL and RIF can maintain it as OWL. OWL syntax has to be a subset of RIF.

Frank
: Preserve procedural attachments.

Deepa
: preserve meta-data in procedural attachments

Michael
: What are we going to do with this now.

Donald
: Two deontic operators

Csma
: RIF must be extensible

Donald
: Metadata
...Real things like a table or column distinction from processing the data.

CSMA
: Rules for machine consumption.
 
Sandro: Requirements are being imposed on the format of RIF and for the processor for RIF.

Harold
: This distinction should be at the top level of the taxonomy.

Break (until 16:00)

(Chair: Chris Welty; Scribe: Markus Kroetzsch)

<ChrisW> mike dean, are you here?

<mdean> yes

Sandro:Previous session of collecting requirements is not satisfying.
... there are many rule systems, but we need to identify common features
... there should be some sharing among similar systems
... e.g. sharing between several different production rulse systems
... Try to establish a framework

csma:agrees. Identify features that can be reused by other systems.
... provide guidance of how to work with unsupported features.

Semantic Web compatibility

(Chair: Chris Welty; Scribe: Markus Kroetzsch)

Chris: Highly important to be compatible with existing Semweb standards
... different possible views:
... (1) OWL as a part of (the syntax of) RIF
... OWL does not get translated
... but is just loaded in RIF without change
... (2) OWL  is a covered/source/target language

Mala:What about other langues such as Common Logic?

Chris:OWL ist a W3C standard, so compatibility is part of the charter.

Harold:I would like to add a third point: (3) interoperation
... meaning that one refers to another (OWL) document which remains external

<josb> As I understood Harold, you include queries to OWL ontologies in the body of the rule

<Scribe> Yes, I think so

Sandro:There might be another aspect of (1): Transforming parts of OWL (e.g. DLP) into a rule syntax.
...Elaboration of point (2):
... * syntax/semantics of OWL in RIF
... * mapping of OWL "Rules"
... (3) dubbed "OWL in a box"

Francois:+1 Harold (i.e. point (3) above)

Hassan:It is not the concern of RIF to specify how to reason with encoded logical specifications. RIF provides the semantics and those who employ RIF must provide their operationalisation.
... It suffices to encode OWL semantics in rules.

Francois:Syntax of course must be compatible or translatable -- but this is secondary.
... Reasoning is more important.
... Reasoning for rule languages is typically constructive.
... Which is simpler than reasoning in other formalisms (no excluded middle, refutation, ...)
... Implementing an OWL reasoner in RIF would not be good.

ChrisWe do not want to do this.

Francois:Translating OWL into RIF does not make sense. (?)

Harold:The expressiveness needed to translate OWL into RIF is not available in Phase 1.

Chris:Any other ideas on Semantic Web compatibility as well?

csma:Can't this be applied to RDF as well?

Harold:We probably mean OWL DL and this refers to a subset of RDF as well.

Chris: I was talking about OWL in general.
...What are the options for RDF and RDFS?

Frank:The case of combining OWL with another rule language is important.
.. e.g. one could combine OWL with Prolog
... and this combined language might have a different mapping to RIF

Chris:Mapping OWL into Prolog is lossy already.

Frank:It might be possible to have non-lossy combinations.

Chris:It seems that it would then be possible to use a uniform mapping.

Francois:Rule languages often have no disjunctive reasoning.
... and translating C \sqsubseteq A\sqsup B might be problematic
... since a lossy translation "A <- C" is not useful

Chris:Why should a rule language not have disjunctions in the head?

Francois:Such rule languages do not seem useful, since they might be incompatible to existing languages.

Sandro:Full FOL is in scope for Phase 2.

csma:If there is an implemented rule language that allows disjunction in the head, then we can decide on whether we want to cover these or not. We do not question the language.

<Scribe> Discussion on whether OWL syntax should be part of RIF.

Chris:This may conflict with the requirement of having a nice syntax.

Deepa:If OWL/XML is part of RIF, does every RIF-conformant processor have to support OWL?

Chris:No. This is not required, since hardly any system can be expected to support all languages captured by RIF.

Sandro:The label "sublanguage" [used by Chris earlier] was replaced early on by the idea of "modules" in the charter.
... So one can have systems conforming to some RIF module.

Sergio:Not every OWL-DL document is an RDF document. The syntactic way in which OWL-DL is defined is not very simple. Including it directly in RIF might cause unpleasant definitions of syntax.

Chris:The basic question is: should there be a "special treatment" for OWL, or is it just treated as any other language we support?

Sandro:The options (2) (a) [OWL semantics in RIF, new syntax] and (b) [OWL translated into rules, that are more expressive than Horn] are available for any language.

Francois:Theory Reasoning/Theory Resolution might also be a general option.

Hassan:This formalism was made obsolete by Constraint Programming.

Christine:What does "greater-than-Horn expressivity" mean in point (2)(b)?
... will we end up with a super-set approach when supporting many languages in this way?

Chris:OWL has a special status that other languages *may* not have.

Francois:We are at the crossing point of this WG!
... Two choices:
... (i) RIF is a language which has disjunctive rules (disjunction in heads). This has advantages (great expressiveness), but also disadvantages: you may not find efficient reasoners.

Sandro:There might be more reasoners in the future.
... It must not be our concern at the moment.

Francois:It is still dangerous. we might come up with things that are not supported by any usable reasoner. It might not be realizable in practical systems.
... this is rather a reasearch topic.

Chris:We do not require that there are reasoners for RIF.

Francois:Second approach:
... (ii) We can look around at best practices in Computer Science.
.. there are currently three kinds of rules.
... Database-like rules, Integrity constrainst, and reactive rules
... So one should look at existing tools to find what is useful in practice.

Chris:Let us turn our findings into something concrete.

<Scribe> ACTION: Francois writes down the details of his proposal. [recorded in http://www.w3.org/2006/02/28-rif-minutes.html#action10]

Chris:Other approaches to Semweb compatibility?

PFPS:You could relax the requirement of having "OWL/XML" as a syntactical embedding of OWL into RIF.
... so why not admit another syntax, such as OWL abstract syntax.

Chris:This is not an option since OWL/XML is the only syntax for OWL Full.

<Scribe> Show of hands

Chris:Who thinks (1) is the way to support OWL?

<Scribe> -> 1 person

Francois:In FOL you often have a placeholder for terms, whereas in OWL you leave terms implicit.
... I like both. So maybe we can keep both options?
... you can choose either way, or try to combine both.
... Description Logic has another cultural style than FOL.
... There might be problems of combining the two.

Michael:Clarification: (1) was embedding without translation, and (2) (a) includes a new syntax for OWL?

csma:Yes.

Chris:So there a two styles, one based on modal logic that shows not terms, the other in FOL with explicit terms.
... but the modal syntax can be mapped to FOL.
... So it probably not that hard to map one style to the other.

<Scribe> Chris provides more clarification concerning the different between (2) (a) and (b).

Chris:Who thinks that (2) (a) is the way for RIF to be compatible with OWL?

<Scribe> -> 7 people

Chris:Who thinks that (2) (b) is the way for RIF to be compatible with OWL?

<Scribe> -> 15 people

Chris:Who thinks that (3) is the way for RIF to be compatible with OWL?

<Scribe> -> 18 people

csma:In (2) (b) OWL implementers seem to have to do the work, while in (a) we seem to have to do it. That is why I prefer (b).

MichaelKNobody has to do the work.

SergioThe works by Eiter and Rosati are examples for (3).
... both are possible.

Igor:I had a different undertanding of (3).
... Wasn't (3) more like SPARQL?

Chris:No, rather not.

JosB:If you have a FOL sublanguage of RIF, then (2) is possible. But in a Logic Programming setting, you have to restrict to (3).

Chris:Any other comments? [none]
... Another aspect of the compatibility discussion are URIs.

PFPS:We should use IRIs

Sandro:I think we can still say "URIs"

Chris:So to what part are URIs part of RIF?
...Should all our symbols be URIs?

Francois:The URI issue seems to be important for reasoning on the web.
... Another aspect is privacy of data. So can we restrict RIF rules to some part of the Web?
... Something similar is possible in RDF. There one can include statements.

[General disagreement: there is no import/include in RDF]

Sandro:URIs are used both as names and as locations.
... RDF never uses them as addresses. We have to be careful to distinguish this.

Chris:To the commercial rule vendors:
... would it be a limitation to have to use URIs for every symbol in RIF?

PaulV:This is just a mapping issue. No major problem.

Francois:The possibility of hiding is very important. It might be useful for us.
... (hiding as in Software Engineering)

Sandro:We would need a serious reason for supporting this.
... It seems to be complicated.

<josb> +1

Frank:The descision that some identifiers are the same can be complicated in some logical systems.
... So requiring that every URI is a different thing affects reasoning.

Chris:E.g. in OWL this is not assumed.

Harold:more about RDF
...bnodes, see wiki
...binary/ternary relations, ...
... mappings; correspondence of RDFS and RIF

Chris: any burning issues?

Conclusion

csma: major achievements: use cases ...
... design goals ...
... moving toward technical spec
... thanks the scribes :-)
... minutes as fast as possible
... reminds us of schedule
... telecon in two weeks: uc
... lots of actions
... closing statement: thanks everybody
... see you next time

Summary of Action Items

TO BE Completed with ACTIONs SCRIBED OFF-LINE!!!!!

[NEW] ACTION: AxelP to set up logistics F2F page [recorded in http://www.w3.org/2006/02/28-rif-minutes.html#action07]
[NEW] ACTION: Francois writes down the details of his proposal. [recorded in http://www.w3.org/2006/02/28-rif-minutes.html#action10]
[NEW] ACTION: Frank to make his point on the mailing list [recorded in http://www.w3.org/2006/02/28-rif-minutes.html#action08]
[NEW] ACTION: Francois to contact Ian about the change of the use case [recorded in http://www.w3.org/2006/02/28-rif-minutes.html#action01]
[NEW] ACTION: Harold to explain technically the basis for interoperation between PR and Horn rules [recorded in http://www.w3.org/2006/02/28-rif-minutes.html#action09]
[NEW] ACTION: JeffPan propose extension to prescription example [recorded in http://www.w3.org/2006/02/28-rif-minutes.html#action03]
[NEW] ACTION: JohnH to reflect that title in the new proposed text [recorded in http://www.w3.org/2006/02/28-rif-minutes.html#action05]
[NEW] ACTION: JohnHall come up with new text by Monday [recorded in http://www.w3.org/2006/02/28-rif-minutes.html#action04]
[NEW] ACTION: Michael to provide some specific comments of 2.8 [recorded in http://www.w3.org/2006/02/28-rif-minutes.html#action02]
[NEW] ACTION: Sandro to organize such WBS vote [recorded in http://www.w3.org/2006/02/28-rif-minutes.html#action06]
[NEW] ACTION: PFPS to ask Ian to make changes to use case
[NEW] ACTION: Frank to effect Proposal 2 (remove data integration from 2.1, retitle, and revise, ensuring that there are rules there)
[NEW] ACTION: Sandro to effect Proposal 3 as modified
[NEW] ACTION:
Allen as editor of UCR to remove 2.6
[NEW] ACTION: Chris to tell Leora to make changes
[NEW] ACTION: PFPS to make proposal on Wiki for ISWC, Athens, Nov 2006

 
[End of minutes]