Difference between revisions of "Base Metrics"

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(Data property count)
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Base Metrics comprise of simple metrics, like the counting of classes, axioms, objects etc.
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Base Metrics comprise of simple metrics, like the counting of classes, axioms, objects etc. These metrics show the quantity of ontology elements.
 
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So it shows the quantity of ontology elements.
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The difference between the count metrics and the total count metrics is, that the total count metrics takes account of imports from other ontologies.
 
The difference between the count metrics and the total count metrics is, that the total count metrics takes account of imports from other ontologies.
  
For these Metrics we chose:
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For the base metrics we chose:
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==Axiom==
 
==Axiom==
Axioms are basic statements of an ontology, they are used to obtain information about classes and properties.
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Axioms are basic statements of an ontology and also the main component, they state what is true in a domain.
Thus they are used to connect class and property identifiers to their specification.
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It is possible to have axioms for classes, properties, datatype definitions, assertions and annotations.
  
 
==Class==
 
==Class==
Classes in ontologies are concepts, these classes can contain other classes or individuals.
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Classes in ontologies are concepts, these classes can contain other classes or individuals. In other words, a class is a set of individuals.
 
In OWL exists a Thing-Class, which is a universal class, so every user defined class is a subclass of the Thing-Class.
 
In OWL exists a Thing-Class, which is a universal class, so every user defined class is a subclass of the Thing-Class.
  
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==Individuals==
 
==Individuals==
  
Individuals are the instances of the classes, so they represent the actual object.
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Individuals are the instances of the classes, so they represent the actual object of the domain.
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Tehere are two types of individuals: named- and anonymous individuals.
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Named individuals have a explicit name and can be used in every ontology for the same object, while anonymous individuals are used local, only in one ontology.
 
This metric counts these instances, one class is able to have a set of instances.
 
This metric counts these instances, one class is able to have a set of instances.
  
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#''http://www.enzyklopaedie-der-wirtschaftsinformatik.de/lexikon/daten-wissen/Wissensmanagement/Wissensmodellierung/Wissensreprasentation/Semantisches-Netz/Ontologien''
 
#''http://www.enzyklopaedie-der-wirtschaftsinformatik.de/lexikon/daten-wissen/Wissensmanagement/Wissensmodellierung/Wissensreprasentation/Semantisches-Netz/Ontologien''
 
#''https://www.w3.org/TR/owl-ref/''
 
#''https://www.w3.org/TR/owl-ref/''
#''https://www.w3.org/TR/2004/REC-owl-semantics-20040210/syntax.html''
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#''https://www.w3.org/TR/owl2-syntax/''

Revision as of 10:44, 17 June 2016

Base Metrics comprise of simple metrics, like the counting of classes, axioms, objects etc. These metrics show the quantity of ontology elements.

The difference between the count metrics and the total count metrics is, that the total count metrics takes account of imports from other ontologies.

For the base metrics we chose:

Axiom

Axioms are basic statements of an ontology and also the main component, they state what is true in a domain. It is possible to have axioms for classes, properties, datatype definitions, assertions and annotations.

Class

Classes in ontologies are concepts, these classes can contain other classes or individuals. In other words, a class is a set of individuals. In OWL exists a Thing-Class, which is a universal class, so every user defined class is a subclass of the Thing-Class.

With this metric we count the classes, including the thing-class, to create a view on the quantity of classes.

Individuals

Individuals are the instances of the classes, so they represent the actual object of the domain. Tehere are two types of individuals: named- and anonymous individuals. Named individuals have a explicit name and can be used in every ontology for the same object, while anonymous individuals are used local, only in one ontology. This metric counts these instances, one class is able to have a set of instances.

Property

In OWL there are two types of properties:

Object property

Object properties link individuals to individuals.

Data property

Other then the Object properties the Data properties link individuals to data values (literals).

Sources

  1. http://www.enzyklopaedie-der-wirtschaftsinformatik.de/lexikon/daten-wissen/Wissensmanagement/Wissensmodellierung/Wissensreprasentation/Semantisches-Netz/Ontologien
  2. https://www.w3.org/TR/owl-ref/
  3. https://www.w3.org/TR/owl2-syntax/