1. Ontology development in Protégé

2. Lecture 2 Introduction to Protégé 2 Pablo Romero, Department of Informatics Overview Components of an ontology The ontology development process  Six basic steps Protégé  Classes  Properties

3. Lecture 2 Introduction to Protégé 3 Pablo Romero, Department of Informatics A development method 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

4. Lecture 2 Introduction to Protégé 4 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?

5. Lecture 2 Introduction to Protégé 5 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

6. Lecture 2 Introduction to Protégé 6 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)

7. Lecture 2 Introduction to Protégé 7 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

8. Lecture 2 Introduction to Protégé 8 Pablo Romero, Department of Informatics Classes in Protégé All classes are subclasses of Thing Classes overlap by default! Can use tools menu to create class hierarchies

9. Lecture 2 Introduction to Protégé 9 Pablo Romero, Department of Informatics Properties in Protégé Object or data type Properties can have  Subproperties  Inverse properties

10. Lecture 2 Introduction to Protégé 10 Pablo Romero, Department of Informatics Properties in Protégé Properties can be  Functional  Transitive  Symmetric  Asymmetric  Reflexive  Irreflexive

11. Lecture 2 Introduction to Protégé 11 Pablo Romero, Department of Informatics Domains and ranges Axioms not constraints  Can lead to inconsistencies Inverse properties are updated automatically

12. Lecture 2 Introduction to Protégé 12 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?

13. Lecture 2 Introduction to Protégé 13 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

14. Lecture 2 Introduction to Protégé 14 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

15. Lecture 2 Introduction to Protégé 15 Pablo Romero, Department of Informatics Resources Protégé website:  http://protege.stanford.edu/ http://protege.stanford.edu/ Protégé tutorial  http://www.co-ode.org/resources/tutorials/ProtegeOWLTutorial-p4.0.pdf http://www.co-ode.org/resources/tutorials/ProtegeOWLTutorial-p4.0.pdf Ontology development methodology  http://www-ksl.stanford.edu/people/dlm/papers/ontology-tutorial-noy- mcguinness.pdf http://www-ksl.stanford.edu/people/dlm/papers/ontology-tutorial-noy- mcguinness.pdf Sample ontologies  http://www.co-ode.org/ontologies/ http://www.co-ode.org/ontologies/