Top Level OntologiesOntologies and Ontology Engineering

Ekhiotz Vergara and Maria VasilevskayaDept. of Computer & Information Science

Linköping University

14th June 2011

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Outline

Introduction Definition Goals Main principle Some existing ontologies

Upper Level Distinctions Selected ontologies

Cyc DOLCE SUMO

Application of Upper Ontologies Merging or Upper Ontologies Results of comparison

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Outline

Introduction Definition Goals Main principle Some existing ontologies

Upper Level Distinctions Selected ontologies

Cyc DOLCE SUMO

Application of Upper Ontologies Merging or Upper Ontologies Results of comparison

14/6/11

Definition

“An attempt to create an ontology which describes very general concepts that are the same across all domains. The aim is to have a large number on ontologies accessible under this upper ontology” [Wikipedia]

“The very first kind” [Philosophical view]

Similar concepts: Top, Foundation, Upper

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Goals

Semantic interoperability To interpret information properly by the receiving system in

the same sense as intended by the transmitting systems

Ontologies matching/alignment To find correspondence among sets of ontologies

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Ontologies communication

Main principleOntology communication

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Domain ontology A

Domain ontology B

Domain ontology C

Upper ontologyUpper ontology

CategoriesCategories

refer to refer to refer to

Specific

terms

Abstract

terms

refer to

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Some existing ontologies

DOLCE (Descriptive Ontology for Linguistic and Cognitive Engineering)

SUMO (Suggested Upper Merged Ontology) BFO (Basic Formal Ontology) GFO (General Formal Ontology) Cyc PROTON (PROTo ONtology) Sowa’s ontology

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Outline

Introduction Definition Goals Main principle Some existing ontologies

Upper Level Distinctions Selected ontologies

Cyc DOLCE SUMO

Application of Upper Ontologies Merging or Upper Ontologies Results of comparison

14/6/11

Aristotle’s categories

Influence in the current understanding of ontologies Kategoria

Kinds of predicates/predication

Different interpretations 10 categories:

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Individuals and categories

Individuals: entity that cannot be instantiated Examples:

Category: Dog, Electron, Red… Individual: the red of an apple, my dog Wolfy..

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IndividualIndividualCategoryCategoryInstance-of

Time and space

Time points and intervals Ontologies based on time points

Ontologies based on intervals Time intervals meet other intervals

Mixed approach, time intervals and boundaries Brentano-time Boundaries can coincide

Spatial point and region

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Time

a b(a,b)

e(a,e) )e,b)

Objects and processes

Based on a space and time ontology, different categories of individuals can be derived

Ontologies with time points as primitives Continuant / endurant:

Persistence through time Identity condition property assigned to identify it Instance of an continuant at some time point

Occurrants: Temporal, unfold through time E.g. processes

Continuants may participate in continuants

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Objects and processes

Ontologies based on time intervals Temporally extended objects as primitives and derive objects

at time points General Process Theory All entities temporally extended

E.g. properties as layer of processes

Ontologies based on mixed approach Brentano-time/space Presentials in the boundaries Persistance category to define identity criteria over time

Abstract entities Independent of space and time

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Examples

Basic Formal Ontology Non-abstract individuals Real numbers to model time and space Continuants and occurrants

DOLCE Individuals, abstract and concrete Real numbers to model time and space Continuants, occurrants and abstract individuals

General Formal Ontology Categories and individuals Brentano-time/space Processes, presentials and abstract individuals Classification of ontological categories

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Outline

Introduction Definition Goals Main principle Some existing ontologies

Upper Level Distinctions Selected ontologies

Cyc DOLCE SUMO

Application of Upper Ontologies Merging or Upper Ontologies Results of comparison

14/6/11

Cyc

“Formalised representation of facts, rules of thumb and heuristics for reasoning about objects and events of everyday life”

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DOLCEDescription

Descriptive Ontology for Linguistic and Cognitive Engineering

Semantic Web Cognitive bias

Natural language Human commonsense

Mesoscopic level Descriptive

Assist in making already formed conceptualizations explicit

Particulars (individuals) Distinction between:

Continuants Occurrents

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DOLCETop level

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DOLCERefined top level

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SUMO

Suggested Upper Merged Ontology

The largest formal public ontology

Created by merging several ontologies: Sowa’s upper-level ontology Russell and Norvig’s upper-level ontology James Allen’s temporal axioms Casati and Varzi’s formal theory and holes …

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SUMOHigh Level Distinctions

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SUMO ontology

• Engineering Components• Geography• Government • Military• Finance• …

• Communication, • Distributed Computing• Countries and Regions,• Economy, • North American Industrial

Classification System

MILO (Mid-Level Ontology)

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SUMOHigh Level Distinctions

‘Physical’ (things which have a position in space/time) and ‘Abstract’ (things which don’t)

Partition of ‘Physical’ into ‘Objects’ and ‘Processes’

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Entity

PhysicalAbstract

Physical

Objects Processes

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SUMOTop Level Structure

Physical

Object

SelfConnectedObject

Substance

CorpuscularObject

Region

Collection

Process

DualObjectProcess

InternalChange

ShapeChange

IntentionalProcess

Motion

Abstract

SetOrClass

Relation

Proposition

Quantity

Number

PhysicalQuantity

Attribute

Graph

GraphElement

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SUMOValidation

Mapping to all of WordNet lexicon A check on coverage and completeness (at a given

level of generality) Peer review

Open source since its inception Formal validation with a theorem prover

Free of contradictions (within a generous time bound for search)

Application to dozens of domain ontologies

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Outline

Introduction Definition Goals Main principle Some existing ontologies

Upper Level Distinctions Selected ontologies

Cyc DOLCE SUMO

Application of Upper Ontologies Merging or Upper Ontologies Results of comparison

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Applications

Automatic ontology matching Finding correspondences between entities belonging to two

or more ontologies

DOLCE LOIS project SmartWeb Language Technology for eLearning AsIsKnown

SUMO More than 100 papers using it Mostly in linguistics

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Outline

Introduction Definition Goals Main principle Some existing ontologies

Upper Level Distinctions Selected ontologies

Cyc DOLCE SUMO

Application of Upper Ontologies Merging or Upper Ontologies Results of comparison

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Merging Upper Level Ontologies

COSMO (COmmon Semantic MOdel) Lattice of ontologies that will serve as a set of basic logically-

specified concepts that can be specified in domain ontologies

Contains: OpenCyc SUMO Some concepts of DOLCE and BFO

MSO (Multi-Source Ontology) Large knowledge server

Lexical ontology

OntoMap Semantic framework on conceptual level No maintenance

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Outline

Introduction Definition Goals Main principle Some existing ontologies

Upper Level Distinctions Selected ontologies

Cyc DOLCE SUMO

Application of Upper Ontologies Merging or Upper Ontologies Results of comparison

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Results of comparison

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Results of comparison

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References

Mascardi, V.; Locoro, A.; Rosso, P.; , "Automatic Ontology Matching via Upper Ontologies: A Systematic Evaluation," Knowledge and Data Engineering, IEEE Transactions on , vol.22, no.5, pp.609-623, May 2010

Ian Niles and Adam Pease. 2001. Towards a standard upper ontology. In Proceedings of the international conference on Formal Ontology in Information Systems - Volume 2001 (FOIS '01), Vol. 2001.

Viviana Mascardi, Valentina Cordì and Paolo Rosso. A comparison of upper ontologies. Technical report. 2006

Aldo Gangemi, Nicola Guarino, Claudio Masolo, Alessandro Oltramari, and Luc Schneider. 2002. Sweetening Ontologies with DOLCE. In Proceedings of the 13th International Conference on Knowledge Engineering and Knowledge Management. Ontologies and the Semantic Web (EKAW '02), Springer-Verlag, London, UK, 166-181.

D. B. Lenat and R. V. Guha. Building large knowledge-based systems: representation and inference in the cyc project. Journal of Artificial Intelligence. 1990.

Pierre Grenon and Barry Smith and Louis Goldberg. Biodynamic Ontology: Applying BFO in the Biomedical Domain. 2004.

Ontogenesis. What is an upper level ontology? 2011. Ludger Jansen. Chapter 8, Categories: The top-level ontology.

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Thanks!

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