1. Methontology: From Ontological art to Ontological Engineering
A lecture by João Cardoso & Sebastião Freire
11/22/2018
Instituto Superior Técnico

2. Instituto Superior Técnico
Table of Contents
Motivation
Ontology Development Process
Ontology Life Cycle
Methontology
Conclusions
11/22/2018
Instituto Superior Técnico

3. Instituto Superior Técnico
Table of Contents
Motivation
Ontology Development Process
Ontology Life Cycle
Methontology
Conclusions
11/22/2018
Instituto Superior Técnico

4. Instituto Superior Técnico
Motivation
Ontologies were being built with different methods and techniques.
There was a need for standardization
11/22/2018
Instituto Superior Técnico

5. Instituto Superior Técnico
Table of Contents
Motivation
Ontology Development Process
Ontology Life Cycle
Methontology
Conclusions
11/22/2018
Instituto Superior Técnico

6. Instituto Superior Técnico
Ontology Development Process
The Ontology Development Process refers to what activities need to be carried out when building ontologies. It comprises the following activities:
Plan
Purpose and Scope
Sources of Knowledge, processes and techniques
Conceptual Model
Formalization
Integrate
Formal Language Implementation
Evaluation
Documentation
Maintenance
1. The main tasks to be done, time and resources needed
2. Why it is being built and intended users
3. Self evident
4. Creation of a conceptual model for the ontology based on the aggregated knowledge
5. Formalize the conceptual model
6. Integrate other ontologies as much as possible
7. Formalize the ontology in a formal representation
8. Evaluate the ontology before publishing
9. Document the ontology for future use and share
10. Maintain the ontology
11/22/2018
Instituto Superior Técnico

7. Instituto Superior Técnico
Table of Contents
Motivation
Ontology Development Process
Ontology Life Cycle
Methontology
Conclusions
11/22/2018
Instituto Superior Técnico

8. Instituto Superior Técnico
Ontology Life Cycle
11/22/2018
Instituto Superior Técnico

9. Instituto Superior Técnico
Table of Contents
Motivation
Ontology Development Process
Methontology
Conclusions
11/22/2018
Instituto Superior Técnico

10. Instituto Superior Técnico
Methontology (1/10)
11/22/2018
Instituto Superior Técnico

11. Instituto Superior Técnico
Methontology (2/10)
Specification
The goal of the specification is to produce either an informal, semi-formal or formal ontology specification document written in natural language, using a set of intermediate representations or using competency questions, respectively.
11/22/2018
Instituto Superior Técnico

12. Instituto Superior Técnico
Methontology (3/10)
Specification
The goal of the specification is to produce either an informal, semi-formal or formal ontology specification document written in natural language, using a set of intermediate representations or using competency questions, respectively.
A good ontology specification document must have the following properties:
Concision
Partial Completeness
Consistency
11/22/2018
Instituto Superior Técnico

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Methontology (4/10)
Specification
11/22/2018
Instituto Superior Técnico

14. Instituto Superior Técnico
Methontology (5/10)
Conceptualization
During the conceptualization task the domain knowledge will be structured into a conceptual model that describes the problem and its solution in terms of the domain vocabulary identified in the ontology specification task.
The product should be a glossary of terms, which includes concepts, instances, verbs and properties. This identifies and gather all the useful and potentially usable domain knowledge and its meanings.
11/22/2018
Instituto Superior Técnico

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Methontology (6/10)
Conceptualization
Data Dictionaries – describes and gathers all potentially usable domain concepts, their meanings attributes, instances, etc.
Tables of Instance Attributes – provide information about the attribute or about its values at the instance
Tables of Class Attributes – describe the concept itself and not its instances
Tables of Constants – specify the information related to the domain of knowledge that always takes the same value
Tables of Instances – define instances
Attributes Classification Trees – geographically display attributes and constants related in the inference sequence of the root attributes.
Verbs Dictionary – expresses the meaning of verbs in a declarative way
Tables of Conditions – Specify a set of conditions to be satisfied before executing an action, or set of conditions
11/22/2018
Instituto Superior Técnico

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Methontology (7/10)
Integration
Definitions built in other ontologies might be used to speed up the creation process. As such it is necessary to perform integration.
Inspect the meta ontologies to see those that fit better in our conceptualization
Find out which libraries of ontologies provide definitions of terms whose semantic and implementation is coherent with yours
Integration document summarizes the meta-ontology that I will use for each and every term.
11/22/2018
Instituto Superior Técnico

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Methontology (8/10)
Implementation
The implementation task implies formalizing the meta-ontology and ontologies selected in the integration task.
The result should be a ontology codified in a formal language.
11/22/2018
Instituto Superior Técnico

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Methontology (9/10)
Evaluation
Evaluation means to carry out a technical judgement of the ontologies, their software environment and documentation with respect to a frame of reference (in this case the requirements specification document) during each phase and between phases of their life cycle.
The outcome of the evaluation should be several evaluation documents in which the ontologist will describe how the ontology has been evaluated, the techniques used and the kind of errors found in each activity.
11/22/2018
Instituto Superior Técnico

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Methontology (10/10)
Documentation
There were no consensuated guidelines on how to document ontologies. Methontology aims to solve this by including documentation in every activity in the ontology development process.
11/22/2018
Instituto Superior Técnico

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Table of Contents
Motivation
Ontology Development Process
Methontology
Conclusions
11/22/2018
Instituto Superior Técnico

21. Instituto Superior Técnico
Conclusions
Identified a set of activities to be perfomed during the ontology development process.
Proposes the evolving prototype as the life cycle that best fits the ontology life cycle.
Defines the Methontology, a methodology that aims to structure ontology creation.
11/22/2018
Instituto Superior Técnico

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References
M. Fernández-López, A. Gómez-Pérez, N. Juristo. “Methontology: from ontological art towards ontological engineering”
11/22/2018
Instituto Superior Técnico