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Re: Publications about OWL (1 or 2) Full

From: Michael F Uschold <uschold@gmail.com>
Date: Tue, 21 Jun 2011 22:27:23 -0700
Message-ID: <BANLkTinyp=DrY=Fu1N2UBMikYqWctUAfAA@mail.gmail.com>
To: Markus Krötzsch <markus.kroetzsch@comlab.ox.ac.uk>
Cc: antoine.zimmermann@insa-lyon.fr, semantic-web@w3.org
Excellent, thanks for the reference to the ISWC paper!
Michael

On Mon, May 23, 2011 at 10:54 PM, Markus Krötzsch <
markus.kroetzsch@comlab.ox.ac.uk> wrote:

> On 19/05/11 20:40, Michael F Uschold wrote:
>
>> I just tried the simple Eagle example in Topbraid Composer.  The tool
>> prevents me from entering Eagle both as a class and as an instance of
>> Species, but I can do it manually in a text file, upload it and the
>> SPARQL works as intended.
>>
>> However, is it pure SPARQL, no OWL inferencing. So this happens
>> independently of any OWL 2 DL entailment regime.
>>
>
> Besides David's earlier mail on Composer, I am pretty sure that Protege
> supports punning as well. Current DL reasoners usually have no problem
> handling this feature.
>
>
>
>> I'll have to go poke arodn a bit more to see what if anything the OWL 2
>> DL entailment regime buys me in this context.
>>
>
> A more recent, OWL-centric publication on meta-modelling came to my mind
> now:
>
> Birte Glimm, Sebastian Rudolph, Johanna Völker:
> Integrated Metamodeling and Diagnosis in OWL 2
> ISWC 2010, http://www.aifb.kit.edu/web/**Inproceedings3124<http://www.aifb.kit.edu/web/Inproceedings3124>
>
> This is a more comprehensive discussion of the meta-modelling features that
> one can practically express in OWL 2, both directly and indirectly.
>
> Cheers,
>
> Markus
>
>
>  On Thu, May 19, 2011 at 12:25 PM, Michael F Uschold <uschold@gmail.com
>> <mailto:uschold@gmail.com>> wrote:
>>
>>    ON the Eagle Example:
>>
>>        :Species a owl:Class .
>>        :Eagle a :Species, a owl:Class ;
>>        rdfs:subClassOf :Animal .
>>        :billy a :Eagle .
>>
>>        This is valid OWL 2 DL.
>>
>>        Then, with a SPARQL 1.1 query with OWL 2 DL entailment regime, I
>>        can get
>>        the pairs <species,**individualmemberofthespecies>:
>>
>>        SELECT ?species, ?member WHERE {
>>        ?species a :Species .
>>        ?member a ?species .
>>        }
>>
>>
>>    >  Yes, this is allowed.
>>
>>    So if this returns ?species as Eagle and ?member as Billy, then
>>    SPARQL must not know it is only a pun. It thinks the two are the
>>    same. Maybe it is just a syntactic link with little or no semantic
>>    import.Intriguing. I'll have to try this out.
>>
>>    This is a bit better than I thought. Thanks for the clarification.
>>
>>
>>    On Thu, May 19, 2011 at 12:01 PM, Markus Krötzsch
>>    <markus.kroetzsch@comlab.ox.**ac.uk <markus.kroetzsch@comlab.ox.ac.uk>
>>    <mailto:markus.kroetzsch@**comlab.ox.ac.uk<markus.kroetzsch@comlab.ox.ac.uk>>>
>> wrote:
>>
>>        On 19/05/11 18:58, Antoine Zimmermann wrote:
>>
>>            First, thanks to you Michael and Markus for your replies.
>>
>>            Now, Michael,
>>
>>        <snip>
>>
>>
>>
>>                    Fortunately, OWL 2 now allows a useful form of
>>                    simple meta-modelling
>>                    now,
>>                    so that you can indeed have meta classes and use
>>                    classes as subjects and
>>                    objects of properties.
>>
>>
>>                The logical inferences that OWL 2 DL tools draw from
>>                this are limited,
>>                but
>>
>>                    may still be more than what any particular OWL 2
>>                    Full reasoner would
>>                    give
>>                    you (depends on the OWL 2 Full reasoner you have --
>>                    I am not aware of
>>                    much
>>                    implementation work there beyond OWL 2 RL).
>>
>>
>>                Hmm, I know there is some limited punning, but these are
>>                two different
>>                things, not one thing appearing in two different places.
>>                The inference is
>>                very limited.
>>
>>
>>            What Markus says here I guess is that, in spite of the
>>            limitations of
>>            the punning mechanism, a full-fledged OWL 2 DL reasoners
>>            will likely
>>            infer more things than *currently existing* incomplete OWL
>>            Full reasoners.
>>
>>
>>        Right. We know that there cannot be a tool that computes all
>>        consequences of OWL with "proper" meta modelling, and we also
>>        know that some forms of meta modelling can even lead to
>>        intricate inconsistencies that make the whole ontology language
>>        paradoxical (PF Patel-Schneider's paper "Building the Semantic
>>        Web Tower from RDF Straw" alludes to this issue). So it seems
>>        that a tool that obtains all consequences of plain OWL
>>        constructs, and that can still handle some meta modelling is not
>>        such a bad choice, even if it is called "OWL DL reasoner" ;-)
>>
>>
>>
>>
>>                I don't think there is a way to nicely handle the
>>                species example where
>>                Species is a class with instance Eagle with instances
>>                being individual
>>                eagles.
>>
>>
>>            No problem:
>>
>>            :Species a owl:Class .
>>            :Eagle a :Species, a owl:Class ;
>>            rdfs:subClassOf :Animal .
>>            :billy a :Eagle .
>>
>>            This is valid OWL 2 DL.
>>
>>            Then, with a SPARQL 1.1 query with OWL 2 DL entailment
>>            regime, I can get
>>            the pairs <species,**individualmemberofthespecies>:
>>
>>            SELECT ?species, ?member WHERE {
>>            ?species a :Species .
>>            ?member a ?species .
>>            }
>>
>>
>>        Yes, this is allowed.
>>
>>
>>
>>
>>                I also do not think there is a robust solution to the
>>                classes as values
>>                problem.
>>
>>
>>            What do you mean by "classes as values problem"?
>>
>>
>>                    An insightful discussion of meta modelling semantics
>>                    -- the one of
>>                    OWL 2 DL
>>                    (punning) and a stronger one -- is found in the paper:
>>
>>                    Boris Motik. On the Properties of Metamodeling in
>>                    OWL. Journal of
>>                    Logic and
>>                    Computation, 17(4):617–637, 2007.
>>
>>
>>                Thanks, I just had a look. It is intersting, and geared
>>                more for the
>>                theorist than the practitioner. Do you know of a more
>>                practice-focused
>>                paper that gives examples of what you can and cannot do
>>                with OWL2
>>                metamodelling, compared to OWL-Full?
>>
>>
>>        Indeed, this paper is more on the logical side of the
>>        discussion, though I still found it quite accessible.
>>        Especially, it has some examples of consequences that one looses
>>        under the weak meta modelling of OWL 2.
>>
>>        I am not aware of a treatment of this issue that is using OWL or
>>        RDF terminology. This may not make it easier to understand,
>>        since the issues of metamodelling are often complicated by
>>        nature -- the straw tower paper mentioned above uses the RDF
>>        data model but still requires some thought to understand the key
>>        issues raised there.
>>
>>
>>
>>
>>                    A big advantage of OWL 2 DL in this respect is that
>>                    it makes it legal to
>>                    state such meta-knowledge without violating any
>>                    constraints of the
>>                    language.
>>                    The OWL Full semantics may still formally lead to
>>                    more consequences,
>>                    but in
>>                    practice what matters is how many of the total
>>                    consequence any tool will
>>                    actually give. So the DL approach could be a good
>>                    compromise
>>                    (especially to
>>                    "make meaning clear" beyond purely logical/formal
>>                    aspects).
>>
>>
>>                I'm not sure what you mean by "make meaning clear" as a
>>                good DL
>>                compromise.
>>                The example from that paper is the need to represent
>>                Eagle as an instance
>>                of Species so you can e.g. say it is on the engangered
>>                list. DL forces
>>                you
>>                to represent Eagle as an as an individual that can not
>>                ever have any
>>                instances. But this is patently untrue -- to that
>>                extent, it obfusticates
>>                meaning. If OWL2 metamodellign lets me do this, I'll be
>>                surprised and
>>                delighted.
>>
>>
>>            Punning means that you can use the URI of an individual in
>>            place of the
>>            URI of a class. Therefore, :Eagle, as a class, can have
>>            instances (like
>>            :billy above) and as an individual it can belong to a class
>>            (like
>>            :Species). However, :Eagle-the-individual is different from
>>            :Eagle-the-class, although they share the same identifier.
>>
>>
>>        Exactly. This is of course a cheap form of meta modelling, but
>>        it seems that it goes a surprisingly long way in practice. Many
>>        use cases are really about modelling several "layers" of the
>>        domain of interest, but have only little interaction between
>>        these layers. Here is an example where one would see the
>> limitation:
>>
>>        Assume you have Eagle and Hawk as classes, and you have an
>>        individual Tweety who is said to have the species Eagle, and to
>>        have the species Hawk (as individuals). Assume further that
>>        there is a cardinality restriction that requires "has species"
>>        to be functional. Then implicitly we derive that Eagle and Hawk
>>        are the same individuals. With punning, nothing else happens.
>>        With "true" meta modelling, the classes Eagle and Hawk would
>>        also be inferred to be the same, with all the consequences that
>>        this could have.
>>
>>        I am not sure if this is a practically relevant limitation.
>>
>>        Cheers,
>>
>>        Markus
>>
>>
>>
>>
>>                    I think the more important case where ontologies go
>>                    beyond OWL DL is
>>                    due to
>>                    the structural constraints related to transitivity
>>                    and property
>>                    chains (e.g.
>>                    it is easy to get forbidden cycles in property chain
>>                    dependencies).
>>                    But the
>>                    interesting difference to the earlier meta-modelling
>>                    limitations of
>>                    OWL 1 DL
>>                    is that in these cases, the semantics of OWL DL is
>>                    in principle still
>>                    meaningful and well-defined in its common
>>                    first-order logic
>>                    framework. It is
>>                    simply known that computing consequences of this
>>                    semantics becomes
>>                    undecidable, and thus the decidability-loving DL
>>                    tools reject the inputs
>>                    right away.
>>
>>                    But again anybody who would venture to implement OWL
>>                    Full reasoning
>>                    could
>>                    also look into "OWL DL reasoning for ontologies
>>                    violating the structural
>>                    restrictions." This task might be easier to solve in
>>                    practice since one
>>                    could probably reuse existing algorithms and tools
>>                    to solve part of the
>>                    problem. It is also part of ongoing research to
>>                    weaken the structural
>>                    restrictions further, so one already knows of
>>                    complete algorithms
>>                    that could
>>                    achieve this in some cases that OWL DL excludes.
>>
>>                    Also note that "FULL" and "DL" now refer to
>>                    syntactic languages only.
>>                    The
>>                    semantic distinction is now made between "direct
>>                    semantics" and
>>                    "RDF-based
>>                    semantics". This helps a bit to avoid confusion
>>                    between syntax and
>>                    semantics. So my last remark was about finding ways
>>                    to evaluate (more
>>                    of)
>>                    OWL 2 FULL under direct semantics.
>>
>>                    Cheers,
>>
>>                    Markus
>>
>>
>>                        I have no hard evidence, but I feel certain that
>>                        there are plenty of
>>                        cases when the penalties of OWL Full are on
>>                        balance small enough
>>                        compared to the gains of expressive convenience
>>                        and clarity of OWL
>>                        Full.
>>
>>                        I would love to see someone look into this. I
>>                        would love it if someone
>>                        tried to create a reasoner that handled OWL Full
>>                        as efficiently as
>>                        possible.
>>
>>                        Notice how many responses you got to this
>>                        message in the past few
>>                        weeks?
>>                        That may reflect how much people in the
>>                        community care about OWL Full!
>>
>>                        Michael
>>
>>                        Michael
>>
>>                        On Sat, Apr 23, 2011 at 1:05 AM, Antoine Zimmermann
>>                        <antoine.zimmermann@insa-lyon.**fr<antoine.zimmermann@insa-lyon.fr>
>>                        <mailto:antoine.zimmermann@**insa-lyon.fr<antoine.zimmermann@insa-lyon.fr>
>> >
>>                        <mailto:antoine.zimmermann@**insa-lyon.fr<antoine.zimmermann@insa-lyon.fr>
>>                        <mailto:antoine.zimmermann@**insa-lyon.fr<antoine.zimmermann@insa-lyon.fr>>>>
>> wrote:
>>
>>                        Dear all,
>>
>>
>>                        I'm looking for scientific publications related
>>                        to OWL Full. I'm
>>                        interested in the following kind of work:
>>                        - reasoning with OWL Full;
>>                        - modelling ontologies in OWL Full;
>>                        - properties of OWL Full, or relationships
>>                        between OWL Full and
>>                        other formalisms.
>>
>>                        I've found some papers about modelling existing
>>                        ontologies in OWL
>>                        (for instance, modelling a UML spec or a
>>                        frame-based ontology in
>>                        OWL) which happen to fall into OWL Full, but
>>                        nothing about modelling
>>                        OWL Full ontologies by design. I found very
>>                        little about reasoning
>>                        in OWL Full (with the notable exception of [1],
>>                        which also relates
>>                        OWL reasoning to OOP).
>>                        But the vast majority of papers mentioning OWL
>>                        Full present it as
>>                        the language that must be avoided at all cost
>>                        (usually saying "if we
>>                        do that, we are in OWL Full" implying "if we do
>>                        that, we're screwed!").
>>
>>                        Thanks in advance for your pointers.
>>
>>
>>                        [1] Seiji Koide and Hideaki Takeda. OWL-Full
>>                        Reasoning from an
>>                        Object Oriented Perspective. In R. Mizoguchi, Z.
>>                        Shi, and F.
>>                        Giunchiglia (Eds.): ASWC 2006, LNCS 4185, pp.
>>                        263–277, 2006.
>>                        Springer-Verlag Berlin Heidelberg 2006.
>>
>>
>>                        Regards,
>>                        --
>>                        Antoine Zimmermann
>>                        Researcher at:
>>                        Laboratoire d'InfoRmatique en Image et Systèmes
>>                        d'information
>>                        Database Group
>>                        7 Avenue Jean Capelle
>>                        69621 Villeurbanne Cedex
>>                        France
>>                        Tel: +33(0)4 72 43 61 74
>>                        <tel:%2B33%280%294%2072%2043%**
>> 2061%2074><tel:%2B33%280%294%**2072%2043%2061%2074>
>>
>>                        -
>>                        Fax: +33(0)4 72 43 87 13
>>                        <tel:%2B33%280%294%2072%2043%**
>> 2087%2013><tel:%2B33%280%294%**2072%2043%2087%2013>
>>
>>
>>                        Lecturer at:
>>                        Institut National des Sciences Appliquées de Lyon
>>                        20 Avenue Albert Einstein
>>                        69621 Villeurbanne Cedex
>>                        France
>>                        antoine.zimmermann@insa-lyon.**fr<antoine.zimmermann@insa-lyon.fr>
>>                        <mailto:antoine.zimmermann@**insa-lyon.fr<antoine.zimmermann@insa-lyon.fr>
>> ><mailto:
>>
>>                        antoine.zimmermann@insa-lyon.**fr<antoine.zimmermann@insa-lyon.fr>
>>                        <mailto:antoine.zimmermann@**insa-lyon.fr<antoine.zimmermann@insa-lyon.fr>
>> >>
>>
>>                        http://zimmer.**aprilfoolsreview.com/<http://zimmer.aprilfoolsreview.com/>
>>
>>
>>
>>
>>                        --
>>                        Michael Uschold, PhD
>>                        Senior Ontology Consultant, Semantic Arts
>>                        LinkedIn: http://tr.im/limfu
>>                        Skype, Twitter: UscholdM
>>
>>
>>
>>                    --
>>                    Dr. Markus Krötzsch
>>                    Oxford University Computing Laboratory
>>                    Room 306, Parks Road, Oxford, OX1 3QD, UK
>>                    +44 (0)1865 283529
>>                    <tel:%2B44%20%280%291865%**20283529>
>> http://korrekt.org/
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>        --
>>        Dr. Markus Krötzsch
>>        Oxford  University  Computing  Laboratory
>>        Room 306, Parks Road, Oxford, OX1 3QD, UK
>>        +44 (0)1865 283529 <tel:%2B44%20%280%291865%**20283529>
>>
>>        http://korrekt.org/
>>
>>
>>
>>
>>    --
>>    Michael Uschold, PhD
>>        Senior Ontology Consultant, Semantic Arts
>>        LinkedIn: http://tr.im/limfu
>>        Skype, Twitter: UscholdM
>>
>>
>>
>>
>> --
>> Michael Uschold, PhD
>>    Senior Ontology Consultant, Semantic Arts
>>    LinkedIn: http://tr.im/limfu
>>    Skype, Twitter: UscholdM
>>
>>
>
> --
> Dr. Markus Krötzsch
> Oxford  University  Computing  Laboratory
> Room 306, Parks Road, Oxford, OX1 3QD, UK
> +44 (0)1865 283529    http://korrekt.org/
>



-- 
Michael Uschold, PhD
   Senior Ontology Consultant, Semantic Arts
   LinkedIn: http://tr.im/limfu
   Skype, Twitter: UscholdM
Received on Wednesday, 22 June 2011 05:27:52 UTC

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