Interaction Design Chapter 6
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Transcript Interaction Design Chapter 6
Ontology development in
Protégé
Overview
• Components of an ontology
• The ontology development process
Six basic steps
• Protégé
Classes
Properties
Lecture 2 Introduction to Protégé
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Pablo Romero, Department of Informatics
A development method
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Determine domain and scope
Consider re-using
Enumerate important terms
Define classes and class hierarchy
Define properties of classes
Define characteristics of properties
Create individuals
http://www-ksl.stanford.edu/people/dlm/papers/ontology-tutorial-noy-mcguinness.pdf
Lecture 2 Introduction to Protégé
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Pablo Romero, Department of Informatics
Determine domain and scope
• Basic questions
What is the domain the ontology will cover?
What are we going to use the ontology for?
For what types of questions should it provide answer?
Who will use and maintain it?
• Competency questions
Which wine characteristics should I consider when choosing
a wine?
Is Bordeaux a red or white wine?
What is the best choice of wine for grilled meat?
What were good vintages for Napa Zinfandel?
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Pablo Romero, Department of Informatics
Enumerate and hierarchy
• Enumerate
Important terms (wine, grape, winery, location, colour, body, flavour,
fish, red meat, etc.)
Don’t worry about
• Overlap between terms
• Relationships
• Properties
• Define class hierarchy
Look for “independent terms”
Top-down (wine; red, white, rosé)
Bottom-up (Muscadet Sèvre et Maine, Muscadet Coteaux de la Loire,
Muscadet Côtes de Grandlieu; Muscadet)
Combined
Lecture 2 Introduction to Protégé
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Pablo Romero, Department of Informatics
Properties & their characteristics
• Several types of properties
Relationships to other classes (maker of the wine, grape it comes from)
Parts (Courses of a meal)
Simple properties (name, colour, flavour)
• Properties are inherited by subclasses
• Characteristics
Type (for simple properties)
Domains and ranges (winery produces a wine)
Restrictions
• Universal and existential
• Cardinality (how many of them)
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Pablo Romero, Department of Informatics
Protégé
• Free, open source ontology editor
• Allows generation, visualization, and manipulation of
ontologies
• We’ll be working with Protégé-OWL
• Created ontologies can be accessed from Java
programs through the Protégé-OWL API
• Represents
Classes
Properties
Individuals
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Classes in Protégé
• All classes are
subclasses of Thing
• Classes overlap by
default!
• Can use tools menu
to create class
hierarchies
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Properties in Protégé
• Object or data type
• Properties can have
Subproperties
Inverse properties
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Pablo Romero, Department of Informatics
Properties in Protégé
• Properties can be
Functional
Transitive
Symmetric
Asymmetric
Reflexive
Irreflexive
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Pablo Romero, Department of Informatics
Domains and ranges
• Axioms not constraints
Can lead to inconsistencies
• Inverse properties are updated automatically
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Pablo Romero, Department of Informatics
A family tree ontology
• Basic questions
What is the domain the ontology will cover? Family relations
What are we going to use the ontology for? Store family trees
For what types of questions should it provide answer? Queries about
family members
Who will use and maintain it? NA
• Competency questions
Is your uncle your ancestor?
Are Queen Elizabeth II and Phillip related?
Who is their common ancestor?
How many children did George V have?
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Pablo Romero, Department of Informatics
The family ontology
• Develop
Enumerate important terms
Define classes and class hierarchy
Define properties of classes
• Implement in Protégé
Create class hierarchy (disjoint classes?)
Create property hierarchy (characteristics, disjoint)
Establish domains and ranges
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Pablo Romero, Department of Informatics
Key points
• Ontology elements
Classes
Properties
Individuals
• Development steps
Determine domain and scope
Consider re-using
Enumerate important terms
Define classes and class hierarchy
Define properties of classes and their characteristics
Create individuals
• Protégé allows the implementation of ontologies in an interactive
way
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Pablo Romero, Department of Informatics
Resources
• Protégé website:
http://protege.stanford.edu/
• Protégé tutorial
http://www.co-ode.org/resources/tutorials/ProtegeOWLTutorial-p4.0.pdf
• Ontology development methodology
http://www-ksl.stanford.edu/people/dlm/papers/ontology-tutorial-noymcguinness.pdf
• Sample ontologies
http://www.co-ode.org/ontologies/
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Pablo Romero, Department of Informatics