See also: IRC log
<ChrisW> updated minutes of last week's meeting can be found at: [http://lists.w3.org/Archives/Public/public-rif-wg/2006Apr/0036.html]
Hassan: points out that minutes don't make sense at some point(s) because the chronology is unclear
IanH: suggests that the chronolgy can be put back together like in a jiggsaw-puzzle
Hassan: doubts whether jiggsaw-puzzle can be accepted
Chris: explains how "+1" is always difficult,
<pfps> +1 :-)
Christian: advises scribes to add stuff as long as it's fresh in their mind.
<Deborah_Nichols> volunteers to send some amplification from my notes
Hassan no longer objects
<ChrisW> +1 to ian
IanH suggest to wait with "+1" until scribe has scribed
<MoZ_> +1 to make clearer +1
<Zakim> sandro, you wanted to comment on +1 in IRC
ChrisW: asks again for objections to accept the minutes?
Sandro: suggest to "annotate" the "+1"s with what you agree with (as in all the examples above)
<MarkusK> +1 to stating what one agrees to ;-)
ChrisW: minutes are
Christian: raises issue that RIF telecon overlaps with SPARQL telecon because of Boston time/universal time difference
csma: has checked that there are no rules as to which time "pattern" should be used for WGs
csma: suggests that we could switch to UTC, but this will mean 1 hour later.
ChrisW: asks whether anybody wants to stay wrt constant?
<MoZ_> just prefer no overlapping
ChrisW: adds that this means "no summertime"
??? prefers this because otherwise, RIF members can't participate in SPARQL meeting
<csma> ACTION: Christian will investigate overlap with SPARQL [recorded in http://www.w3.org/2006/04/04-rif-minutes.html#action04] [CONTINUED]
JosDeRoo: finds summertime in general annoying
ChrisW: explains that there are two problems: changing to/from summertime and overlap with SPARQL telecon
<pfps> adds that there are places that don't go on summer time at all
ChrisW: isn't sure whether RIF WG's
time is changeable
<csma> ACTION: chair to put design for extensibility and discussion of proposals on agenda for next telecon [recorded in http://www.w3.org/2006/03/28-rif-minutes.html#action14] [DONE]
ChrisW: repeats warning about filling flights to Dubrovnik
<Hassan> +1 to posting a page on travel
ChrisW: suggest to put up a page to register, Sandro?
<PaulaP> we can use the information found at http://www.w3.org/2005/rules/wg/wiki/F2F3/TravelTimes
Sandro: announces that, for registration and also participant's travel times (for co-ordination), he will set up a RIF registration page
<csma> ACTION: Sandro to set up registration page for F2F3 [recorded in http://www.w3.org/2006/04/11-rif-minutes.html#action03]
ChrisW: reminds that ESW conference organizers will organize transfer from the airport, and we need to co-ordinate with them
<AlexK> I can't access the travel times page--not allowed to view this page
<csma> it seems like the W3C site is down
<sandro> AlexK, you need to login to the wiki to get to that page. (BUt that page is now obsolete, if I understand correctly.)
<PaulaP> at moment it is not really clear whether the ESWC organizers will provide such a form
MKifer: are the visa requirements for Montenegro?
<AlexK> Croatia should be fine for most of us
MKifer: and visa for Croatia?
<MarkusK> Btw. Michael Sintek and I are going to Tivat
<PaulaP> there is information on the ESWC web page
<Deborah_Nichols> the country is Serbia and Montenegro. There is no Yugoslavia any more.
<IanH> We couldn't be so lucky as to be unable to go there!
Uli: ask your travel agent!
<AlexK> Have a look above
<igor> visa info for Montenegro
Christian: seems most citizens won't need a visa...
ChrisW: reminds that next week
is deadline for proposals for F2F4, for which there are
currently two proposals
<PaulV> OMG PRR: no news from liason
ChrisW: suggests to start by going through last week's actions
<csma> ACTION: Christian to send email to propose resolution that decidability is a non-requirement and gather relevant arguments before next telecon [recorded in http://www.w3.org/2006/04/04-rif-minutes.html#action14] [DONE]
ChrisW: ...this action on the decidability proposal is continued
<csma> ACTION: Frank will produce an initial diagram with existing constraints [recorded in http://www.w3.org/2006/04/04-rif-minutes.html#action10] [CONTINUED]
csma: was not comfortable with WG
deciding "non-requirements", prefers requirements, etc
... so far, nobody submitted a requirement on decidability,
<csma> ACTION: MickaelK to extend page on pure prolog and give a precise definition (according to standard publications) [recorded in http://www.w3.org/2006/04/04-rif-minutes.html#action13] [DONE]
csma: suggests to come up with a requirement that makes decidability a non-requirement
<DavidHirtle> I think he posted regrets on the wiki
<csma> ACTION: sandro to clarify meaning of sound and what is the requirement on RIF [recorded in http://www.w3.org/2006/04/04-rif-minutes.html#action11] [CONTINUED]
<csma> ACTION: Sandro to clarify whether sound reasoning constraint with unknown dialects is a requirement or a critical success factor [recorded in http://www.w3.org/2006/04/04-rif-minutes.html#action12] [CONTINUED]
ChrisW: Dave's proposal is a good example of a requirement... any comments on this?
csma: if we agree on a requirement/goal/etc., then they should be linked with other things on the web page
<csma> ACTION: Evan to publicize to ODM [recorded in http://www.w3.org/2006/03/28-rif-minutes.html#action09] [DONE]
sandro: we could use Dave's proposal as a "structural example" and have the others follow it
<pfps> Here we are getting into a problem similar to that brought up by Hassan - the log is not close to the timeline of the call
<sandro> Chris: Do we like this CSF Methodology?
chrisW: explains that we only meant the "abstract structure", not the specific proposal
FrankMcCabe: Sees some up-side down thinking and suggests to concentrate on goals before we go to requirements
csma: reminds that requirements can only come with critical success factors
<FrankMcCabe> suggests to mine goals from the charter.
MKifer: seconds FrankMcCabe's suggestions, and observes that Dave's proposal is vague in parts: e.g., "effective" and "sufficiently few dialects", and that he doesn't understand implications of several points in Dave's proposal
<PaulaP> +1 to more clear and detailed constraints
csma: suggests to add details and comments on the wiki
MKifer: suggests to avoid "general words"
csma: suggests to add examples for implementation of a requirement
ChrisW: asks what the relation is between hierarchy and goals and design constraints?
csma: suggests that, in Dave's proposal, there are "dependencies" between these concepts to be added, and that these dependencies will be visualised
ChrisW: sees a representation problem: we would need levels in hierarchy, to have structure between constraints
<Zakim> sandro, you wanted to ask if it's a tree or a lattice?
FrankMcCabe: explains how adding more justifications for a requirement makes it stronger
<sandro> Frank: It's important to know all the reasons why a Requirement is important (ie a lattice)
ChrisW: wants to know how to indicate direction of link?
<sandro> Sandro: I like "Motivation"
<sandro> paste link to what you're loking at, folks.
csma: explains how dependencies work between requirements and critical success factors...
sandro: suggest to make things easier by using an indented list for requirements
<Zakim> sandro, you wanted to suggest a simple way to do the structure
sandro: and to add critical design factors for each requirement explicitly
ChrisW: and link requirements to detailed goals? This would make structure more apparent
ChrisW: explains that we are using this requirement because it's complete, and reads out an example
ChrisW: comments on requirement that RIF-compliant applications must be able to handle rules in a predictable way
csma: suggests that we start discussing requirements with a less complex one
ChrisW: invites comments on "Rif core must cover pure prolog"? And reminds that we already discussed difficulty with "pure prolog"
csma: suggests to remove "core" from this requirement
<sandro> +1 to csma, it's too early to argue that RIF **Core** should cover pure Prolog
csma: would prefer that this is "Rif standard or extended Rif"
<GaryHallmark> +1 to remove core. Core seems by definition the intersection of the other requirements
csma: would prefer, in general, to be a bit more open or global wrt different RIFs
pfps: points out that even pure prolog is "very complicated", and suggests to decide whether/where we need to cover pure prolog, and suggests to replace "pure prolog" with "X", for a simpler logic. Also points out that it is inappropriate to talk about ISO standards here, and thus pure prolog is difficult
Igor: explains that all information is found at the prolog wiki page
<PaulaP> +1 to pfps on finding the motivation of using pure prolog here
pfps: questions whether enough information about occurs check can be found there
Igor: suggests to accept MKifer's suggestion to drop pure prolog
ChrisW: suggests to Igor to explain which rules we mean on the wiki, and points out that it's up to the requirement's authors as to whether they require prolog or Horn or...
Igor: suggests to replace pure prolog with "horn clauses"
ChrisW: points out that Horn clauses is not unambiguous either
sandro: asks for new suggestions for a new name to replace "pure prolog" in this requirement?
MKifer: repeats from his email: that pure prolog is horn rules plus ordering
csma: clarifies his previous remark, that requirements shouldn't target specific RIF variants, and that such a discussion should be left to a later point in time because we need to get a complete picture first
<csma> ACTION: Sandro and Igor to find a name+definition for the "pure prolog" requirement that does not mention "pure prolog" [recorded in http://www.w3.org/2006/04/11-rif-minutes.html#action10]
Harold: agrees with MKifer, and suggests "Ordered Horn clauses" because, in pure prolog, both the order of literals and rules is important
<ChrisW> ach harold
<pfps> An interesting page on ISO Prolog is http://pauillac.inria.fr/~deransar/prolog/docs.html. The page seems to indicate that the occurs check is somehow optional, at least in some situations.
<ChrisW> ach\k harold
<Harold> We can now define positively what we converged to mean by "Pure Prolog": "Ordered Horn clause".
<csma> ACTION: Sandro to discuss on email whether the "pure prolog" requirement can be replaced by a "horn logic" requirement or if we need both [recorded in http://www.w3.org/2006/04/11-rif-minutes.html#action11]
JosDeRoo: agrees with Harold, and points out how complicated prolog is (with occurs check and such like)
ChrisW: next design constraint: extended RIF ...
FrankMcCabe: wants to know critical success factor of FOL
<Harold> "Ordered Horn Clauses" could be the result of annotating "Horn Clauses".
<AlexK> I'll just merely say about the FOL that it captures requirements in some applications
Leora: explains that FOL is important because of its expressiveness
<csma> +1 to FOL being impotant because of expressiveness
ChrisW: reminds that we are talking about "critical success factors"
<sandro> perhaps: goal = RIF must be useful for KR ?
Leora: will formulate critical success factor for FO and its expressiveness
<AlexK> do we have meta-definitions of Goal, Requirement, CSF?
MalaM: seconds "RIF should cover FOL"
MKifer: proposes that we apply the same standard to FOL as to pure prologue, and hence to explain exactly what we mean by FOL
<Hassan> +1 with Mike
csma: makes two comments: (1) "extended RIF" will cover everything since it will be extensible; and (2) agrees that FOL is important, and he thinks that it is a critical success factor
<MalaMehrotra> +1 to csma
Leora: asks (procedural) how we come to an agreement on what we mean by FOL
ChrisW: the champions decide what they mean, and then we revise it
MarkusK: wondered in how far "rule set" is compatible with FOL? Do we find "rules in" FOL? That is, can we view any FOL theory as a rule set?
<sandro> Markus: does using the word Ruleset mean we're only talking about part of FOL?
ChrisW: so we need to clarify the relation between "rule set" and FOL
sandro: points out that "FOL" should mean "arbitrary FOL theories"
<sandro> Frank: CSF might be "you have to support KR", FOL is not a CSF
FrankMcCabe: thinks that FOL is not a requirement because it is KR?
<sandro> Frank: as in, "if you can't do FOL, you can't do KR"
FrankMcCabe: doesn't think that FOL is a requirement (but a critial success factor?) since "if you can't do FOL, you can't do KR"
<sandro> Frank: Which aspects, eg universally quanitied variables, etc.
csma: clarified that Frank said that FOL was too specific to be a csf but not specific enough to be a requirement
<AlexK> FOL is quite important for KR appplications, exchanging those between companies is very useful
Frank: suggests that, for example, "we need to express existentially quantified variables" would be more like a csf
<csma> I clarified that Franck said that FOL was too specific to be a csf but not specific enough to be a requirement
<sandro> Frank: it's a short circuit to jump to FOL
Frank: "we need FOL" is to short since FOL is a technology
<Zakim> sandro, you wanted to argue that things like "sorted" don't matter for this purpose
<sandro> Sandro: I think "FOL" is the right level of granularity for this year.
Hassan: is concerned about people claiming that "FOL theories" are "rules"
<LeoraMorgenstern> +1 with sandro
Hassan: there are too many ways to describe the same theory (gentzen, sequents, etc), and wants to know whether RIF is about "(deduction) rule interchange" or "theory interchange"
<sandro> Sandro: I'm just talking about standard, textbook, FOL here, as something we need to support in an extension.
<sandro> LeoraMorgenstern: FOL is a cohesive whole, too, to it's a good point of granularity.
Leora: sees a risk in Frank's suggestion to chop FOL up into lots of "little" requirements since it enables people to choose subsets of these and obtain unintended such subsets
ChrisW: points out importance of clarity in the requirements formulation
Leora: points out the risk of mini-requirements