OntoClean Methodology - PowerPoint PPT Presentation

1 / 69
About This Presentation
Title:

OntoClean Methodology

Description:

CNR - Ontology and Conceptual Modelling Groups ... without being necessarily real, or actual: Peter Pan is not real but is concrete ... – PowerPoint PPT presentation

Number of Views:94
Avg rating:3.0/5.0
Slides: 70
Provided by: alessandro
Category:

less

Transcript and Presenter's Notes

Title: OntoClean Methodology


1
OntoClean Methodology
  • As presented at AOS Workshop by
  • Aldo Gangemi
  • CNR-IP, Ontology and Conceptual Modelling Group

2
Credits
  • CNR - Ontology and Conceptual Modelling Groups
  • Nicola Guarino, Claudio Masolo, Alessandro
    Oltramari
  • Nicola.Guarino,claudio.masolo,alessandro.oltramar
    i_at_ladseb.pd.cnr.it
  • Aldo Gangemi, Domenico Pisanelli, Geri Steve
  • gangemi,pisanelli,steve_at_itbm.rm.cnr.it
  • Vassar College
  • Chris Welty
  • weltyc_at_vassar.edu
  • Publications are retrievable on-line at the
    following URLs
  • http//www.ladseb.pd.cnr.it/infor/ontology/ontolo
    gy.html
  • http//saussure.irmkant.rm.cnr.it/onto/index.html

3
Some Applications so far
  • ON9 ontology library
  • UMLS Metathesaurus semantic mining
  • Medical terminologies integration
  • Integration of Clinical Guidelines Standards
  • Ontological upgrading of Wordnet
  • Ontological Web Agents
  • Product ontologies
  • OntoClean Top-Level
  • Legal ontologies and norm dynamics
  • Portal directories maintenance and subject
    ontology
  • Content standards for the semantic web

4
Some Projects so far
  • GALEN (EU AIM Project, academic/industrial
    project for a medical terminology server)
  • SOLMC (Ontological and Conceptual Modelling
    Tools, CNR Special Project)
  • Arianna Catalog (industrial pilot project to
    build and maintain portal directories)
  • IKF, Intelligent Knowledge Fusion (Eureka Project
    E!2235, academic/industrial project for
    information integration)
  • IIDEAS, Integration of Industrial Data for
    Exchange, Access, and Sharing
  • IEEE Standard Upper Ontology Study Group
  • OntoWeb Ontology-based information exchange for
    knowledge management and electronic commerce (EU
    Network of Excellence)
  • OntoWeb SIG on Content Standards
  • TICCA (Italian Project, Cognitive technologies
    for artificial agents)

5
OntoClean Antecedents
  • Guarino and Weltys theoretical tools for the
    ontological refinement of taxonomies
  • ONIONS techniques for domain ontology development
    and large-scale terminology integration

6
OntoClean Components
  • Formal Criteria
  • Top-Level Ontology
  • Ontology of Universals
  • Domain-Level Development Guidelines
  • Applications

7
OntoClean Components
  • Formal Criteria (brief explanation)
  • Top-Level Ontology
  • Ontology of Universals
  • Domain-Level Development Guidelines
  • Applications

8
Individuals and Concepts
  • The term "meta-property" adopted here is based on
    a fundamental distinction within the domain of
    discourse
  • individuals or particulars vs.
  • concepts or universals
  • Meta-level properties induce distinctions among
    concepts, while object-level properties induce
    distinctions among individuals

9
Rigidity
  • A property is essential to an individual iff it
    necessarily holds for that individual
  • A property is rigid (R) iff, necessarily, it is
    essential to all its instances. A property is
    non-rigid (-R) iff it is not essential to some of
    its instances, and anti-rigid (R) iff it is not
    essential to all its instances
  • Person vs Student

10
Identity
  • A property carries an identity criterion (I) iff
    all its instances can be (re)identified by means
    of a suitable sameness relation. A property
    supplies an identity criterion iff such criterion
    is not inherited by any subsuming property
  • Person vs. Student

11
Dependence
  • An individual x is constantly dependent on y iff,
    at any time, x can't be present unless y is fully
    present, and y is not part of x. Ex Hole/Host
  • A property P is constantly dependent (D) iff,
    for all its instances, there exists something
    they are constantly dependent on.
  • Here Dependent Constantly Dependent

12
Types vs. Roles
  • A rigid property that supplies an identity
    criterion and is not (notionally) dependent is
    called a type.
  • An anti-rigid property that is notionally
    dependent is called a role. It is a material role
    if it carries (but not supplies) an identity
    criterion, and a formal role otherwise.
  • Person vs. Student vs. Part

13
Extensionality
  • An individual is said to be extensional iff,
    necessarily, everything that has the same proper
    parts is identical to it
  • A property is extensional (E) iff, necessarily,
    all its instances are extensional
  • A property is anti-extensional (E) iff,
    necessarily, all its instances are
    non-extensional, so that they can possibly change
    some parts while keeping their identity

14
Concreteness
  • An individual is concrete iff it has a physical
    location. A property whose instances are
    necessarily concrete will be marked with the
    meta-property C
  • Note that an individual can be concrete without
    being necessarily real, or actual Peter Pan is
    not real but is concrete
  • This meta-property is a bit less formal (in the
    ontological sense) than the previous ones, since
    it makes an ontological commitment towards the
    existence of physical (spatial, temporal or
    spatio-temporal) locations. We see physical
    locations as primitive qualities that individuals
    can have

15
Unity
  • An individual is unified by a (suitably
    constrained) relation R iff it is a mereological
    sum of entities that are bound together by R. Ex.
    the relation having the same boss may unify a
    group of employees in a company
  • An individual w is a whole under R iff it is
    maximally unified by R, in the sense that R is
    internal to w, and no part of w is linked by R to
    something that is not part or w
  • A property P is said to carry unity (U) if there
    is a common unifying relation R such that all the
    instances of P are essential wholes under R. A
    property carries anti-unity (U) if all its
    instances can possibly be non-wholes. If every
    instance of P is an essential whole, but there is
    no unifying relation common to all instances of
    P, then we mark P with the property U

16
Singularity and Plurality
  • An individual is a singular whole iff its
    unifying relation is the transitive closure of
    the relation "strong connection", like that
    existing between two 3D regions that have a
    surface in common. Topological wholes of this
    kind have a special cognitive relevance, which
    accounts for the natural language distinction
    between singular and plural
  • A plural individual is a sum of singular wholes
    that is not itself a singular whole. Plural
    individuals may be wholes themselves or not. In
    the former case they will be called collections
    in the latter case pluralities
  • A piece of coal is a singular whole. A lump of
    coal is a topological whole, but not a singular
    whole, since the pieces of coal merely touch each
    other, with no material connection. It is
    therefore a plural whole

17
Applying Formal Properties
  • If a property holds necessarily for all the
    instances of a certain concept, of course its
    negation cannot hold necessarily for all the
    instances of a subsumed concept.
  • Then, if F is a certain formal property, anti-F
    cannot subsume F anti-rigidity cannot subsume
    rigidity, anti-unity cannot subsume unity, and
    anti-extensionality cannot subsume
    extensionality.
  • After labeling every concept in a taxonomy with
    its formal properties, we can easily check its
    ontological consistency

18
OntoClean Components
  • Formal Criteria
  • Top-Level Ontology
  • Ontology of Universals
  • Domain-Level Development Guidelines
  • Applications

19
The OntoClean Top-Level Ontology an Overview
20
Basic Design Guidelines for the OntoClean
Top-Level
  • Introduction of ontological categories lying
    behind Natural Language and Human Commonsense
  • Use of formal properties (general and neutral as
    possible) to characterize the ontological
    categories
  • Rigidity, Identity, Dependence, Unity,
    Extensionality, Singularity, Concreteness (see
    next slide for references)
  • Refinement of top-distinctions by further
    analysis (taking into account philosophy,
    cognitive sciences, linguistics,)
  • IMPORTANT All top-concepts are considered to be
    rigid, as they
    are assumed to reflect essential
    properties of their instances

21
Brand New Essential Bibliography
  • Guarino and Welty 2001,
  • Supporting Ontological Analysis of Taxonomic
    Relationships (Data and Knowledge Engineering -
    in press)
  • Identity and Subsumption (In R.Green, C. Bean and
    S.Myaeng eds., The Semantics of Relationships
    an Interdisciplinary Perspective. Kluwer - in
    press)
  • Gangemi, Guarino, Masolo, Oltramari 2001,
  • Understanding Top-Level Ontological Distinctions
    ( Proceedings of IJCAI 2001 workshop on
    Ontologies and Information Sharing)
  • Gangemi, Guarino, Oltramari 2001,
  • Conceptual Analysis of Lexical Taxonomies The
    Case of WordNet Top-Level (Proceedings of FOIS
    2001)

22
(1) The Top-Level Unique Beginners, Direct
Hyponyms, Some Synsets from WordNet 1.6
  • Aggregate (D, U)
  • Amount of matter (E)
  • Arbitrary collections
  • Object (D, U)
  • Extensional Body (E)
  • Ordinary Object (E)
  • Event (D, E)
  • Feature (D, U, -E)
  • Relevant part
  • Dependent Region
  • body substance, mixture1, mass5
  • universe1, elementary particle
  • artifact, land4,(unitary) collection1
  • phenomenon, act2, state4
  • edge3, skin1, paring2
  • opening10, excavation3

23
(2) The Top-Level Unique Beginners, Direct
Hyponyms, Some Relevant Synsets from WordNet 1.6
  • Abstraction (C)
  • Abstract entity
  • Proposition
  • Set
  • ...
  • Quality space
  • Color space
  • Shape space
  • Quality (D,E,U)
  • Color
  • Shape
  • ...
  • conclusion5, lemma1
  • union7, singleton2
  • chromatic color
  • shape2

24
(1) Aggregate vs. Object
  • What distinguishes an object from an aggregate is
    that the former is an essential whole, namely it
    has a unity criterion, while the latter is not.
    For example, John can make-up a snowman
    (object) starting from the scattered snow (amount
    of matter) covering his courtyard, adding a hat,
    a carrot, two deadwoods, etc. In general, amounts
    of matter are mass-nouns (you cant say a snow, a
    water, ...), while objects are count-nouns (such
    as a snowman, five glasses of water,and so on).

25
(2) Aggregate vs. Object
  • Arbitrary collections are just mere sum of wholes
    which are not themselves essential wholes (as the
    collection of goods in a bazar). In this sense,
    they are kinds of aggregate. On the other hand,
    there are collections which are themselves
    essential wholes, as a library. In our top-level
    these unitary collections are to be conceived as
    a specialization of the object category.

26
(3) Aggregate vs. Object
  • An object can change some parts, keeping or not
    its identity. In the first case, we call it
    Ordinary Object (E), in the second case
    Extensional Object (E). My car will continue to
    be the same even if I replace one of its wheels.
    On the contrary, if I consider the universe,
    removing a single elementary particle I wont
    have the universe any more, but a different
    entity.
  • Regarding aggregates, we can say that amounts of
    matter are clearly E, while arbitrary
    collections can be considered as
    pseudo-extensional (changes in the parts of a
    member of a collection may be allowed).

27
Event
  • Events occur in time. They are assumed to be
    dependent (D) on those objects (D) that are
    their partecipants.
  • The penalty kick by Roberto Baggio (?main
    partecipant)
  • Partecipants are not parts of events. Parts of
    events can be
  • temporal (the first movement of a symphony)
  • spatial (the strings playing within a symphony)
  • Parts of events are always essential, which means
    that events are extensional (E).
  • Our taxonomy of events needs to be
    improved and populated. A comparison
    with EuroWordNet and SIMPLE, in
    this sense, may be useful.

28
Feature
  • Features are parasitic (D) entities, that
    exist insofar their host exists. Features may be
    relevant parts of their host, like a bump in a
    road, or dependent regions, such as a hole in a
    piece of cheese, the underneath of a table, or
    the shadow of a tree (which are not parts of
    their hosts). All features are essential wholes,
    but no common unity criterion may exist for all
    of them (U). Some features can change parts
    keeping their identity, while some others not
    for this reason, we use -E as the common formal
    property (E and E are both subsumed by -E).

29
Abstraction
  • Abstractions are entities that are not concrete,
    that is, they do not have a physical location
    (C). Quality spaces are the first examples of
    abstractions time, geometric space, length,
    color, are all conceptual spaces, with different
    topological structure. Terms like red, long,
    sweet, old, recent etc. correspond to regions in
    a quality space. We can therefore describe the
    structure of a quality space with a first-order
    theory, using topological notions for instance,
    we can say that red is adjacent to brown. Other
    examples of Abstraction are propositions, sets,
    symbols, etc.

30
Quality (1)
  • Qualities are always qualities of something in
    this sense, they are dependent (D). Qualities
    are individual, i.e. that they are inherent to a
    unique entity (the color of this rose is red). We
    call quality-type every homogenous group of
    individual qualities, such as color, shape,
    volume, etc. In the OntoClean top-level qualities
    are structured in strict relationship with
    quality spaces every quality-type corresponds
    to a quality space in the branch of Abstractions.
    A region in a quality space corresponds to an
    individual quality of an entity in our
    conceptualization of the world.

31
Quality (2)
  • Following our approach, the red of the rose on
    the right figure is represented as located in a
    certain region in the colors-quality-space. In
    the same way, the spherical shape of the ball
    below is represented as located in a certain
    region of the shape-quality-space. In principle,
    time and space could be treated as qualities too.
    We are currently studying the ontological
    commitments and the formal properties concerning
    this options.

32
Appendix An Alternative View of the OntoClean
Top-Level (1)
  • Since the agreement on the meaning of general
    categories is not always easy, in this short
    presentation we preferred to make clear first the
    most relevant top-level concepts, leaving aside
    the various ways they can be presented in a
    hierarchy. For example, we could have introduced
    the OntoClean top-level by considering the
    general distinction between concrete and abstract
    entities as the complete partition of what there
    is in the world. Then, within concrete entities
    we could have distinguished independent from
    dependent entities. The overall taxonomy would
    have been like this

33
Appendix An Alternative View of the OntoClean
Top-Level (2)
  • Quality (E,U)
  • Color
  • Shape
  • Abstraction (C)
  • Abstract entity
  • Proposition
  • Set
  • ...
  • Quality space
  • Color space
  • Shape space
  • Concrete (C)
  • Independent (D)
  • Aggregate ( U)
  • Amount of matter (E)
  • Arbitrary collections
  • Object ( U)
  • Extensional Body (E)
  • Ordinary Object (E)
  • Dependent (D)
  • Event ( E)
  • Feature ( U, -E)
  • Relevant part
  • Dependent Region

34
OntoClean Components
  • Formal Criteria
  • Top-Level Ontology
  • Ontology of Universals (list of main kinds)
  • Domain-Level Development Guidelines
  • Applications

35
Which part are you talking about?
  • If my liver is part of my digestive system, and
    that system is part of me, is my liver part of
    me?
  • If my liver is a part of me and I am part of the
    CNR, is my liver part of the CNR?
  • My liver is a component of my digestive system,
    while I am a member of CNR. No rule for composing
    component and member relations
  • Moreover, I am a body, but I am also a person. A
    living person depends on a body. Nevertheless, a
    living person can be a member of CNR, but a body
    cannot

36
Ontology of Universals - Main Relation Kinds -
  • Intracategorial
  • Mereological (entity, entity)
  • Topological (entity, entity)
  • Intercategorial
  • Localization (region, entity)
  • Participation (event, entity)
  • Representation (sign, entity)
  • Entrenched axiomatic characterisation

37
OntoClean Components
  • Formal Criteria
  • Top-Level Ontology
  • Ontology of Universals
  • Domain-Level Development Guidelines (hints)
  • Applications

38
Kinds of Terminological Ontology Sources
  • Catalog of normalized terms, e.g. a list of terms
    used in the reports from a laboratory no
    taxonomy, no axioms, and no glosses
  • Glossed catalog, e.g. a dictionary a catalog
    with glosses.
  • Thesaurus, e.g. many parts of the UMLS
    Metathesaurus, GEMET a hierarchical collection
    of terms the hierarchical link is usually
    polysemous
  • Taxonomy, e.g. the ICD10 a collection of classes
    with a partial order induced by inclusion
    (classification)
  • Axiomatized taxonomy, e.g. the GALEN Core Model
    a taxonomy with axioms
  • Ontology library, e.g. the Ontolingua repository
    a set of axiomatized taxonomies with relations
    among them. Each element of the library is a
    module, which can be included into another one.
    Also, a concept from a module can be only used
    into another one. Ontology modules can be
    considered subdivisions of the namespace of a
    model

39
Impairments in Traditional Terminologies
  • Lack of hierarchies
  • Ambiguous hierarchies
  • Informality
  • Lack of modularity or cyclic taxonomical
    dependencies between modules
  • Polysemy of various sorts
  • Uncertain semantics
  • Ontological opaqueness
  • Lack of a (minimal) set of axioms
  • 'Remainder' partitions
  • 'Exception' partitions
  • Terminological cycles
  • Meta-level soup (individuals mixed up with
    universals or even higher order concepts)
  • Low maintenance capabilities

40
Ontologies some desiderata
  • An explicit taxonomy with subsumption among
    concepts
  • Semantic explicitness of relations
  • Rigorous modularity of namespace
  • A stratified design of the modules
  • Absence of polysemy within a module
  • Disjointness of rigid concepts within a module
    and within the top-level
  • A proper interface between the ontology namespace
    and one or more sets of lexical realizations
  • Linguistically meaningful naming policy
    (cognitive transparency)
  • Rich documentation
  • Some (minimal) axiomatization to detail the
    difference among sibling concepts
  • Explicit linkage to concepts and relations from
    generic theories
  • Meta-level assignments to distinguish among the
    formal primitives assigned to concepts
  • Languages and implementations that support the
    previous needs as well as the possibility of
    collaborative modeling

41

ONtologic Integration Of Naïve Sources

42
Lexical and Linguistic Analysis
  • Morpho-semantic analysis (extraction of
    sematically meaningful units)
  • Functional informational structures (extraction
    of head/modifier syntagmatic structures)
  • Conceptual polysemy treatment (templates for
    systematic ambiguity resolving)

43
Conceptual Issues in Ontology Integration
  • Ontology integration is generally speaking
    the construction of an ontology C that formally
    specifies the union of the vocabularies of two
    other ontologies A and B
  • To be sure that A and B can be integrated at some
    level, C has to commit to both A's and B's
    conceptualizations. In other words, the intension
    of the concepts in A and B should be mapped to
    the intension of C's concepts
  • Unfortunately, this cannot be realized using only
    the conceptual relations specified in A and B for
    local tasks (for a specific context). The
    methodological principle adopted here is that
    generic ontologies reused from the philosophical,
    linguistic, mathematical, AI literature must
    found the comparison of different intensions. Our
    approach may be called principled conceptual
    integration

44
Ontology Library Architecture
45
Aspects of integration
  • Three aspects of an ontology are taken into
    account
  • the intended models of the conceptualizations of
    its vocabulary
  • the domain of interest of such models, i.e. the
    'topic' of the ontology
  • the namespace of the ontology
  • The most interesting case is when A and B are
    supposed to commit to the conceptualization of
    the same domain of interest or of two overlapping
    domains. In particular, A and B may be

46
The main steps (I)
  • 0. Semantically opaque hierarchies and lists are
    pre-processed in order to create clean
    taxonomies
  • 1. All concepts, relations, templates, rules, and
    axioms from a source ontology are represented in
    the ONIONS formalisms, currently Loom,
    Ontolingua, and OKBC
  • 2. When available, plain text descriptions are
    analyzed and axiomatized (text formalization)
  • 3. The union of such products is integrated by
    means of a set of generic ontologies. This is the
    most characteristic activity in ONIONS, which can
    be briefly described as follows

47
II
  • 3.1. For any set of sibling concepts in a
    taxonomy, the conceptual difference between each
    of them is inferred, and such difference is
    formalized by axioms that reuse the relations and
    concepts already in the library. If no concept is
    available to represent the difference, new
    concepts are added to the library
  • 3.2. For any set of polysemous senses of a term,
    different concepts are stated and placed within
    the library according to their topic and to the
    available modules. (Polysemy occurs when two
    concepts with overlapping or disjoint intended
    models have the same name.)
  • 3.3. Often, polysemous senses of a term - as well
    as different 'alternative' concepts - are
    metonymically related. For example
    process/outcome (as in inflammation),
    region/object (as in body region), etc.
    Alternatives must be properly defined by making
    it explicit the relationship between them e.g.
    "has-product" for inflammation, "location" for
    body-region
  • 3.4. When stating new concepts, the relations
    necessary to maintain the consistency with the
    existing concepts are instantiated. If conflicts
    arise with existing theories, a more general
    theory is searched which is more comprehensive.
    If this is impracticable, an alternative theory
    is created

48
III
  • 3.5. Relevant integration cases. Since ONIONS
    requires the use of generic theories to
    axiomatize alternative theories, the integration
    of a concept C from an ontology O is performed by
    comparing C with the concepts D1,,n already
    present in the evolving ontology library L, whose
    ontology set M1,,n contains at least a
    significant subset of generic ontologies and the
    set of domain ontologies at that state in the
    evolution of L. The following cases appear
    relevant to the methodology
  • 3.5.1. C's name is polysemous in O (internal
    polysemy). Iterate 3.2 3.4
  • 3.5.2. C's name is homonym with the name of a Di.
    (Homonymy occurs when both the intended models
    and the domains of two concepts with the same
    name are disjoint.) Homonyms must be
    differentiated by modifying the name, or by
    preventing the homonyms to be included in the
    same module namespace
  • 3.5.3. C's name is synonym with the name of a Di.
    (Synonymy is the converse of homonymy and occurs
    when two concepts with different names have both
    the same intended model and the same domain.)
    Synonyms must be preserved, or included in the
    set of lexical realizations related to the
    concept
  • 3.5.4. C is subsumed by some Di in L, but it has
    no total mapping on any Dj in L. The gap in L
    must be filled by adding C as a subconcept of Di

49
IV
  • 3.5.5. C is an intersection between two concepts
    Di and Dj in L. Solved by distinguishing types
    and roles, or different defining elements
  • 3.5.6. C has an alternative concept Di in L (same
    domain, but overlapping or disjoint intended
    models)
  • 3.5.6.1. If C metonymically depends on Di, C is
    properly related to Di
  • 3.5.6.2. If C and Di are different viewpoints on
    the same domain of interest, both concepts are
    kept if the case, they are included in separate
    modules
  • 3.5.6.3. If the intended model of C is finer than
    Di's, Di is substituted with C
  • 3.5.6.4. If the intended model of C is coarser
    than Di's, C is ignored (but track of it is kept
    for mapping between sources)

50
V
  • 4. The library of generic, intermediate, and
    domain ontologies should be stratified, say
    domain modules should include intermediate
    modules - that should include generic modules -
    so that each set of modules can be plugged or
    unplugged from its more general set without
    affecting the coherence of the entire library
  • 5. The source ontologies are explicitly mapped to
    the integrated ontology, in order to allow
    interoperability. The only admitted mappings are
    equivalent and coarser equivalent. Formally for
    any source ontology SO and an ontology IO that is
    supposed to result (also) from the integration of
    SO, for any concept Ci in SO, there is a Di in IO
    such that CiI DiI (equivalence of possible
    interpretations), or there is a disjunctive
    concept (or Di Dj) in IO such that CiI DiI ?
    DjI (equivalence of possible interpretations to a
    disjunction of concepts i.e. to a union of
    finer concepts)
  • 5.1. Partial mappings must have been already
    resolved through the methodology if any, some
    step in the integration procedure must be
    iterated

51
Formal Approach
  • Ontology Integration Framework (Calvanese,DeGiacom
    o,Lenzerini 2001)
  • Description Logic-based
  • Mapping relations between local ontologies
  • Views either globally or locally

52
OntoClean Components
  • Formal Criteria
  • Top-Level Ontology
  • Ontology of Universals
  • Domain-Level Development Guidelines
  • Applications (examples)

53
The OntoWordnet Loom KB
  • We created a Loom KB, containing, for each named
    concept, its direct super-concept(s), some
    annotations describing the quasi-synonyms, the
    gloss and the synset subject assignment, and its
    original numeric identifier in WordNet for
    example
  • (defconcept HorseEquus_Caballus
  • is-primitive EquineEquid
  • annotations ((subject animals)
  • (word horse)
  • (word Equus caballus)
  • (documentation "solid-hoofed herbivorous
    quadruped domesticated since prehistoric times"))
  • identifier 101875414)

54
What can be improved in WordNet
  • Top-level not based on formal ontological
    principles
  • Concepts vs. individuals lack of distinction
  • Object-level vs. meta-level lack of
    distinction
  • Roles vs. types lack of distinction
  • Taxonomies to be revised
  • Multihierarchies
  • Few conceptual relations among synsets
  • Weak subdivision by subject
  • Phrases to be augmented

55
Concepts vs. individuals
  • Under Event, we find Fall (of mankind)
  • Under Territorial_Dominion we find Macao
  • Problem gt Expressivity lack
  • Solution gt We need an instance-of relation

56
Object-level vs. Meta-level
  • The synset Abstraction_1 includes both abstract
    entities, such as Set, Time, and Space, and
    abstractions such as Attribute, Relation,
    Quantity.
  • Abstraction_1 is glossed as "a general concept
    formed by extracting common features from
    specific examples. Abstraction seems to be
    intended therefore as a psychological process of
    generalization. This meaning seems to fit the
    latter group of terms (Attribute, Relation,
    Quantity), but not the former, which would be
    considered as abstract under a different notion,
    namely not being extended in space/time.
  • Solution
  • Attribute, Relation, and Quantity are meta-level
    concepts, while Set, Time, and Space are
    object-level concepts.

57
Role vs. Type
  • RULE gt A role cannot subsume a type
  • Person (that we consider as a type) is subsumed
    by two different concepts, Organism and
    Causal_Agent.
  • Organism can be conceived as a type as well,
    while Causal_Agent as a formal role (inferrable
    from its subconcepts)
  • The first subsumption relationship is therefore
    feasible, while the second one shows a rigidity
    violation (roles are not rigid)
  • Solution gt Maintain meta-property-based views of
    taxonomy

58
Taxonomical Ambiguity in Wordnet
  • Apparently sibling noun phrases are located in
    distant taxonomy branches
  • Solution dissolve heterogeneous branchings by
    analysing complex senses (knowledge is a type,
    communication is a role, social relation is a
    meta-level concept, etc)

59
Wordnets Top Synsets (UBs and some hyponyms)
60
Some more examples
  • Possession_1 is a role, and it includes both
    roles and types
  • Some hyponyms of Physical_Object are mapped to
    Feature
  • Abstraction_1 is the most heterogeneous Unique
    Beginner. It contains abstracts (Set_5), quality
    spaces (Chromatic_Color), qualities (mostly from
    the synset Attribute) and a hybrid concept
    (Relation_1) that contains abstracts, other
    entities, and even meta-level categories
  • Psychological_Feature contains both abstract
    entities (Cognition) and Events (Feeling_1)
  • Event_1, Phenomenon_1, State_1, Act are globally
    mapped to our Event category, although by
    simply looking at their children it seems quite
    hard to explicit any criteria to maintain the
    original distinctions

61
Cleaned-Up WordNet
  • Following OntoClean, we have concentrated first
    on the so-called backbone taxonomy, which only
    includes the rigid properties. Formal and
    material roles have been therefore excluded from
    this preliminary work
  • An extreme heterogeneity appears evident
  • Ex. Entity seems a catch-all class
    (Imaginary_place, Anticipation, Inessential,
    Location, Object, Causal_Agent, etc.)
  • Therefore, we also decided to exclude from the
    top-level cleaning those synsets sharing very few
    hyponyms (resembling orphans), like some of the
    above hyponyms of Entity

62
Revised Top-Level Table
63
Main Types in the Revised Top-Level
64
Ontological Integration Applied to Medical
Terminologies
  • UMLS Metathesaurus Category Intersections
  • UMLS Semantic Network
  • SnoMed Nomenclature
  • ICD10 Classification
  • MeSH Thesaurus

65
Some UMLS concepts pertaining the intersection
Amino Acid, Peptide, or Protein Carbohydrate
  • (hamster oviduct-specific glycoprotein)
  • (Par j I)
  • ((Man)6(GlcNAc)2Asn)
  • (Zn(2)-IAA)
  • (collapsing factor)
  • (BDV 18K glycoprotein)
  • (SI-gene-associated glycoprotein, Nicotiana)
  • (FdI allergen)
  • (sca gene product)
  • (EPV20 protein)
  • (lubricin)
  • (Pluritene)
  • (Par h 1 allergen)
  • (Wnt11 gene product)
  • (I-D-Gal-BSA)
  • (mannose-bovine serum albumin conjugate)
  • (acrosome granule lysin)
  • (sulfatide activator)
  • (vaccinia virus A34R protein)

gt More than 118,000 UMLS concepts (25) are
classified under an intersection
66
Ontological analysis of the intersection (Loom DL
syntax)
  • (defconcept Amino Acid, Peptide, or Protein
    Carbohydrate
  • "834 instances. This conjunct includes two
    sibling types.
  • A protein containing a carbohydrate."
  • annotations ((Sugg.Name "carbohydrate-containin
    g-protein")
  • (onto-status integrated))
  • is-primitive (and protein
  • (some has-component carbohydrate))
  • context substances)

67
Medical Morphologies
  • Names of anatomical morphologies are often
    polysemous
  • Both a condition and the function that caused the
    condition ("inflammation", "ulcer", "fracture",
    "wound", "hyperplasia")
  • Both an object and the function that produced the
    object ("neoplasm", "hemorrhage")
  • Both an object O and the condition created in
    another object O' by O ("obstruction")
  • For example "the fracture has been caused by a
    fall" vs. "the fracture is transverse" "the
    obstruction occurred in the jejunum" vs. "the
    obstruction has been removed"
  • Conceptual analysis puts into evidence other
    issues concerning morphologies
  • The dependence between a morphological condition,
    a function, and the related organ. For example,
    an "ulcer" (as a condition) of a stomach implies
    that the stomach embodies an ulceration function
    (an ulcer as a function)
  • The mereological import of morphologies some are
    featured by an organ, some only by a part of an
    organ. For instance, an "ectopic heart" is wholly
    ectopic, but an "ulcerated stomach" is only
    partly ulcerated

68
Morphologies Analyzed
  • a quality space ("color", "consistency",
    "thickness", "size", "number", "shape")
  • a situation
  • a topologically relevant condition
  • an alteration of connection
  • that creates a configuration (a new property) in
    an object ("fracture", "wound")
  • in the holey interior of an object
    ("obstruction")
  • between several objects ("fusion")
  • an alteration of the boundary between an object
    holey interior and the object complement
  • creating a configuration in the boundary
    ("cavitation", "ulcer")
  • producing a substance flow ("hemorrhage",
    "ulcer")
  • an abnormal placement ("dislocation", "ectopia",
    "absence")
  • a form alteration condition ("deformity",
    "hyperplasia", "hypoplasia")
  • a condition involving the alteration of several
    properties ("inflammation", "eruption")
  • an abnormal, foreign object ("mass", "neoplasm",
    "calculus", "obstruction")

69
Use OntoClean for all your ontology cleaning
needs!
Write a Comment
User Comments (0)
About PowerShow.com