Overview of major differences between Models and Ontologies. a work by Marija Bjekovic, of ee-team.eu, Jan 2011.

1. Relationship between models and
ontologies
Marija Bjekovic

2. Models
• Model is an abstraction of (some part of) reality,
intended for some definite purpose
- Abstraction of details, conceptualization
- Provides a set of statements about reality that must be faithful
(causal connection)
- Pragmatic usage for a certain purpose

3. Models
• Descriptive model – describes the reality but the reality is not
constructed from it
• Prescriptive model – prescribes the structure or behavior of reality
and reality is constructed according to the model => specification
• Reality – domain, language, system…
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4. Ontologies
• “An ontology is an explicit specification of a
conceptualization” (Gruber, 1993)
• “An ontology is a formal, explicit specification of a
shared conceptualization” (Studer et al, 1998)
• Abstraction of details, conceptualization
• Causal connection
• Explicitly defined
• Shared by a group (consensual)
• Formal
• Based on first order logic
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5. Ontologies - expressivity
• Taxonomy
• Thesaurus
• Ontology
• Logical theory
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6. Ontology
Model • Conceptualization
• Causal connection
• Conceptualization • Explicit
• Causal connection • Formal
• Consensual
• Based on first-
order logic
Formality
• By definition, ontologies have to be formal representations
• When supported by OCL, UML models can be created to satisfy
the requirement of formality
• At least domain models have the goal of explicitly representing
domain
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7. Ontology
Model • Conceptualization
• Causal connection
• Conceptualization • Explicit
• Causal connection • Formal
• Consensual
• Based on first-
order logic
Shared/consensual knowledge
• Model is not restricted to the representation of private (non
shared) information.
• In the end…. any model is intended to be means of
communication within a group
• Shared/consensual aspect of the ontology is not precisely
determined in its definition
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8. Ontology
Model • Conceptualization
• Causal connection
• Conceptualization • Explicit
• Causal connection • Formal
• Consensual
• Based on first-
order logic
Common misconceptions (Atkinson et al, 2006)
• Models focus on realization, ontologies do not.
• Ontologies are for run-time knowledge exploitation, models are not.
• Ontologies are for representing web-based information, models are
not.
• Ontologies are formal, models are not.
• Ontologies can support reasoning, models cannot.
• Models use closed world assumptions, ontologies use open world
assumptions.
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9. Model
Ontology
Conceptualization
Causal connection Explicit &
Formal &
Based on first order
logic
&
Standard/universally
applicable knowledge
Distinguishing criteria by (C.Atkinson et al 2006)

10. Selected references
(Atkinson et al., 2006) C.Atkinson, M. Gutheil and K.Kiko, On the
Relationship of Ontologies and Models, Proceedings of the 2nd
International Workshop on Meta-Modelling, WoMM 2006, p.47-60,
2006.
(Assman et al., 2006) U.Assman, S.Zschaler, and G.Wagner,
Ontologies, Metamodels and the Model-Driven Paradigm, In Coral
Calero, Francisco Ruiz, and Mario Piattini (eds.): Ontologies for
Software Engineering and Technology. Springer, 2006.
(Sellers, 2011) B. Henderson-Sellers, Bridging Metamodels and
Ontologies in Software Engineering, The Journal of Systems and
Software 84 (2011), p. 301-313, 2011.
(Parreiras et al., 2007) F.S.Parreiras, S.Staab, A.Winter, On Marrying
Ontological and Metamodeling Technical Spaces, ESEC/SIGSOFT
FSE 2007, p.439-448, 2007.
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11. Selected references
(Gruber, 1993) Thomas R. Gruber, A Translation Approach to Portable
Ontology Specifications, Knowledge Acquisition, 5(2), pages 199-
220, 1993.
(Studer et al., 1998) Studer R., Benjamins VR., Fensel D., Knowledge
Engineering: Principles and Methods, IEEE Transactions on Data
and Knowledge Engineering 25(1-2), pages 161-197, 1998.
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