This is part of F2F1 Minutes
OWL Working Group Meeting Minutes, 06 December 2007
DRAFT. Currently Under Review
See also: IRC log
Structural Specification and Functional-Style Syntax design review
Slides for this session: Media:motik-f2f1.pdf
(Scribe changed to Jeremy Carroll)
Boris presents slides - OWL 1.1 Design Decisions
General Design Principles (slide 3)
- extend expressivity
- Bring spec closer to tools. Some features of OWL 1.0 have not been implemented correctly.
- make spec cleaner and clearer
Structural Specification: slides 4 and 5
Every OWL API wants to provide "what are the classes in this ontology", but what does that mean for OWL?
Discussion of mention; use; definition? It is very difficult to decide between these.
Jeremy Carroll: why does this matter?
Bijan Parsia: if we can improve interop on this, we should ...
Alan Ruttenberg: if these are design criteria they should be exposed
Boris Motik: there are some explicit answers in the new spec
Boris Motik: W3C should care, because these things are implicit
Peter Patel-Schneider: I still haven't heard a useful answer for tool designers
Alan Ruttenberg: two people are looking at some ontology in two different lists - "please look at class FooBar ..."
Peter Patel-Schneider: but there's lots of example where two different UIs are difficult to interop
Jeremy Carroll: let's have tests
Bijan Parsia: serialization tests would be good -
Bijan Parsia: users care abotu serialization
Bijan Parsia: OWL API
Ratnesh Sahay: a java program on two different dev environments, my program should behave similarly
Ratnesh Sahay: we care more about behaviour of program, than behaviour of tool
Ian Horrocks: the set of classes in an ontology should be well-defined
Michael Smith: for explanation and debugging it is useful to have a mapping from entity or axiom to ontology
Jeremy Carroll: isn't OWL 1.0 clear?
Jeremy Carroll: requires xx rdf:type owl:Class
Boris Motik: e.g. imports or inferred triples
Alan Ruttenberg: what is the underlying design model?
Alan Ruttenberg: If the question is "What classes are mentioned in this ontology?" then we're fine. It's not clear to me that any other question is relevant/important. What motivates other questions?
Boris Motik: we want to design OWL 1.1 as an object model
Matthew Horridge: imports was too vague
Sebastian Brandt: many industrial users like object models; descriptions of triples are much less accessible
someone (maybe Alan): Object oriented modeling of OWL, cuts both ways: A lot of teaching OWL is unteaching object oriented thinking.
expressivity enhancements uncontroversial
Metamodelling (slide 7)
metamodelling needed also in OWL DL
e.g. an OWL-S type example
punning is a possible solution,
applications want syntactic level, and don't want consequences
Peter Patel-Schneider: which reasoners could support Hilog semantics, after minor changes
bijan/boris (guest): easy to modify pellet
Bijan Parsia: easy cases would be easy ...
Jeremy Carroll: huge exlamation on first bullet
Bijan Parsia: OWL Semantics 1.0 is clear, OWL DL name, OWL Full location
Alan Ruttenberg: caching is a tool's issue
Alan Ruttenberg: caching does not break the spec
Bijan Parsia: some implementations change name when ontologies move
Alan Ruttenberg: if I moved ontology from http:... to file:... then I can't import it, and then spec is broken
Alan Ruttenberg: disagrees with first bullet
we agree that we don't agree, but we're not clear what we don't agree on
Bijan Parsia: we have session on annotations
Sebastian (guest): annotations on axioms are useful
Peter Patel-Schneider: all OWL DL reasoners are based on nonnormative docs
(sorry scribe missed a bit)
Bijan Parsia: it would be better if the implementors were working more closely from normative docs
Ian Horrocks: there is no claim that sean's nonnormative doc and normative spec say same thing
discussion on pellet and bnodes --
Alan Ruttenberg: pellet departs from spec
Bijan Parsia: we (pellet team) made choices
(Scribe changed to Pascal Hitzler)
Alan Ruttenberg: interaction of typing with RDF really a problem?
Alan Ruttenberg: is the problem in the language or in the documentation of it?
Bijan Parsia: pellet does some repairs silently. spec could go in a similar direction
Jeremy Carroll: questions on slide 15 answered on OWL 1.0 spec
Boris Motik: some may be, but spec might need fixing or made more explicit
Ian Horrocks: more clear spec desirable
Bijan Parsia: agrees about unclear parts in the spec
review of and resolution to publish Syntax, Semantics, and Mapping-to-RDF documents as First Public Working Drafts
next session: discussion and decisions on publication schedule and first public working draft
chaired by Ian Horrocks
collecting issues: (1) shortname, (2) document titles, (3) SOTD, (4) WIKI extraction, (5) attribution etc.
Ivan Herman: (1) should include namespace
Ian Horrocks: need to decide if namespace is an issue
Bijan Parsia: need to do editorial cleanup (part of (4))
Bijan Parsia: deadlines need to be watched
(1) short name (+ namespace)
suggestions: owlwot, alan: owltoo
Alan Ruttenberg: calling it OWL may overload and thus be difficult
... something neutral to version name?
Sandro Hawke: no problem with same names
Alan Ruttenberg: might be confusing
Sandro Hawke: using same name is only a problem if exactly the same document name is used
Evan Wallace: so why not call it OWL1.1?
Bijan Parsia: OWL1.1 is one possibility
Sandro Hawke: you want a URL which is the link to the latest version of the spec
Evan Wallace: you need a name which redirects to the short name?
Peter Patel-Schneider: eventually pointers to owl1.1 docs might go away ...
... but that's independent of the document names
Ian Horrocks: we can't use "owl-semantics" right now.
Ivan Herman: because that's the working draft
Bijan Parsia: OWLWOT, OWLTOO looks strange
... proposes OWL1.1 or OWL11 or OWL-11
Ian Horrocks: what about OWLTOO
Sandro Hawke: different names suggest different levels of compatibility
Bijan Parsia: OWL1.1 (with any kind of minor changes)
sugestions OWL 1-1, OWL11, OWL-1-1
Ivan Herman: decision has to be formally recorded according to charter
Ian Horrocks: should discuss point (2) at the same time
... what is going to be named in document title?
Alan Ruttenberg: procedural question: can we resolve this here? what about absent people?
Bijan Parsia: explains: may not resolve things which have not been on the agenda
Peter Patel-Schneider: may be arguable
Ivan Herman: was the issue of document titles on the agenda?
some discussion about which things that can be resolved in the F2F
Alan Ruttenberg: supports bijan that we should decide things, and people can appeal to chairs to reopen the issue
Sandro Hawke: in this case: does it need to be decided right now?
Deborah McGuinness: against owl2/owltoo
ian makes straw poll 1.1 against 2 (clear positive outcome for 1.1)
Ian Horrocks: let's decide for 1.1
proposed and resolved: it's going to be 1.1 (in some form)
PROPOSED: Our publications will refer to this work as "OWL 1.1" (not OWL 2.0, etc)
Ian Horrocks: asks for objections, abstantions on that. none recorded
RESOLVED: Our publications will refer to this work as "OWL 1.1" (not OWL 2.0, etc)
Ivan Herman: other specs seem to use similars to OWL11
Sandro Hawke: would like to postpone this and find out some background
Ian Horrocks: straw poll: do we want "owl11" ?
PROPOSED: To ask for shortname "owl11-[whatever]"
Ian Horrocks: what about namespace?
Ivan Herman: tough one
Peter Patel-Schneider: proposes brief discussion about it
Peter Patel-Schneider: should reuse the namespace
several people second reusing the namespace
Alan Ruttenberg: I know now that I don't know whrether to resuse ns
straw poll on this: tendency for reusing namespace, but not uncontroversial
Alan Ruttenberg: if owl constructs change semantics then it may be difficult to reuse name space
Ulrike Sattler: wasn't the idea not to change any of the constructs already present?
Ivan Herman: are we sure this won't happen?
Ian Horrocks: we don't have to decide on this right now
Bijan Parsia: new constructs should have new names
... we will add new things into to the namespace
... expanding vocabulary is considered difficult by some people
Ian Horrocks: summary: tendency for reusing, but issue can be postponed
Peter Patel-Schneider: need to be careful on first working draft that it doesn't cause confusion in terms of namespace
bijan takes action to take care of this
ACTION: Bijan to put alert box in all the documents about the status of the namespace
Alan Ruttenberg: say it "owl" subject to change, not "owl11" subject to change.
Boris Motik: old names are still in old namespace (current document)
Bijan Parsia: suggests to leave the two namespaces as they are right now
Bijan Parsia: let's not make owl 1.1 implementors change anything right now.
Bijan Parsia: there are owl 1.1 ontologies on the web right now.
Alan Ruttenberg: straw poll: leave as is with warnings (agreed)
boris has action to do the changes (add warnings) in the docs
ivan about doc titles: suggests owl11 DL
Ivan Herman: functional syntax doc is DL-only, so that should be in the title?
Ian Horrocks: functional syntax is not entirely irrelevant outside DL
Alan Ruttenberg: needs to be decided later
Ian Horrocks: see 1.0 docs on abstract syntax
Bijan Parsia: in some way structural syntax specifies OWL Full
Ivan Herman: but there are statements which cannot be expressed in it
... should not forget that this is an issue
Ian Horrocks: action on this?
Ivan Herman: need a list of editors first?
moving on to point (5): attribution etc.
Alan Ruttenberg: proposes for current draft that attributions should be as they are
... next draft if substantive changes, attributions should be reevaluated
Bijan Parsia: question is if chairs want to assign editors. bijan suggests chairs do that
Alan Ruttenberg: would like to not do that right now
Peter Patel-Schneider: somebody needs to put more work into it soon ... credit should be given
Ivan Herman: seconds alan: currently mentioned people stay editors for the current version
some more discussion on editors for current version
Bijan Parsia: wants editors assigned now
alan proposes current authors are editors for the current version
Ian Horrocks: should now decide whose job it will be
Ian Horrocks: proposal that boris, peter and bijan work on syntax (they would agree)
Ian Horrocks: bernardo, boris for semantics document? would agree as well
... bernardo, boris would also do the mapping document
... are we happy if they do it?
... straw poll on this: no objections
was agreed that attributions will stay the same in current version of the documents as they are stated right now
Ivan Herman: doesn't it need to be called editor?
Sandro Hawke: I doubt it
Ian Horrocks: If it has to change from author to editor, then that can be chairs decision
moving to point (4): editorial cleanup in the wiki plus wiki extraction
issues from working drafts will stay
Alan Ruttenberg: useful comments should be left but scripted away
moving to point (2): resolution to publish Syntax, Semantics, and Mapping-to-RDF documents as First Public Working Drafts
PROPOSED: Publish Syntax, Semantics, and Mapping-to-RDF documents as First Public Working Drafts
Ian Horrocks: straw poll - no objections
PROPOSED: Publish Syntax, Semantics, and Mapping-to-RDF documents (as on the wiki right now) as First Public Working Drafts
Ian Horrocks: formal vote on this (reminder: only one vote per member): W3C abstains, no objections
RESOLVED: Publish Syntax, Semantics, and Mapping-to-RDF documents (as on the wiki right now) as First Public Working Drafts
moving to (3): SOTD
brief agreement that this shall not be discussed now
Ian Horrocks: lunch break now
Bijan Parsia: thanks to sean for taking care of organisation ...