Difference between revisions of "Base Metrics"

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Base Metrics comprise of simple metrics, like the counting of classes, axioms, objects etc.
 
Base Metrics comprise of simple metrics, like the counting of classes, axioms, objects etc.
 
So it shows the quantity of ontology elements.
 
So it shows 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 these Metrics we chose:
 
For these Metrics we chose:
 
==Axiom==
 
==Axiom==
 
Axioms are basics statements of an ontology, they are used to obtain information about classes and properties.
 
Axioms are basics statements of an ontology, they are used to obtain information about classes and properties.
 
Thus they are used to connect classes and properties identifiers to their specification.
 
Thus they are used to connect classes and properties identifiers to their specification.
 
==Logical axiom ==
 
These special kind of axioms are universally valid.
 
  
 
==Class==
 
==Class==
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With this metric we count the classes, including the thing-class, to create a view on the quantity of classes.
 
With this metric we count the classes, including the thing-class, to create a view on the quantity of classes.
  
===Total class===
 
  
 
==Individuals==
 
==Individuals==
  
Individuals are the instances of the classes. This metric counts these instances, one class could have a set of instances.
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Individuals are the instances of the classes, so they represent the actual object.
 
+
This metric counts these instances, one class could have a set of instances.
===Total Individual===
+
  
  
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[[Object_Property_Axioms|Object properties]] link individuals to individuals.
 
[[Object_Property_Axioms|Object properties]] link individuals to individuals.
  
====Total Object property====
 
  
 
===Data property count===
 
===Data property count===
Other then the Object properties the [[Data_Property_Axioms|Data properties]] link individuals to data values  
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Other then the Object properties the [[Data_Property_Axioms|Data properties]] link individuals to data values (literals).
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====Total data property====
 
  
 
==Sources==
 
==Sources==

Revision as of 21:45, 15 June 2016

Base Metrics comprise of simple metrics, like the counting of classes, axioms, objects etc. So it shows 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 these Metrics we chose:

Axiom

Axioms are basics statements of an ontology, they are used to obtain information about classes and properties. Thus they are used to connect classes and properties identifiers to their specification.

Class

Classes in ontologies are concepts. These classes can contain other classes or individuals. In OWL there a generally 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. This metric counts these instances, one class could have a set of instances.


Property

In OWL there are two types of properties:

Object property

Object properties link individuals to individuals.


Data property count

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/2004/REC-owl-semantics-20040210/syntax.html