Difference between domain and range in rdf schema?

Question

could you please explain me the difference between rdfs:domain and rdfs:range with an example? and when should i use domain and when range? i have read h w3c rdf primer but i did not understand the difference

Cuomo

Answer 1

From a simplistic point of view, the domain and range properties are there to give you insight into the way that the property links a subject to an object.

In the case of the domain property, when you link a subject to an object using a property with this associated attribute, then the subject qualifies as a type of thing specified in the domain. For example, we look at a vocabulary and we see that the domain of our property is a Project. So, simply put, as long as the subject being described using the “name” attribute is a type of project (or could be a type of project), then you should have no problem going ahead using that term to describe that thing, because most other people will interpret that if something is described using this term, then it is a project. You'll find it is not only humans but also machines (or reasoners in this case) that make the same inferences.

The range works exactly like the domain, but with this one, it applies to the object of the statement and not the subject. A word of caution; you might at times come across instances where the domain or range applies to more than one thing. In this case, it means that the subject or object (domain or range) is all of the types specified (the intersection not the union).

Vershen

In more simple terms: "Mother" (domain) hasChild "Child" (range). A more complex example is the Child-Parent relationshipt: "Child" (domain) hasParent "Mother", "Father" (range). Here you have two parents (objects), which are pointed by the child (subject). – Horoscope

Answer 2

I find it easier starting with an example: let's say that we have a property happened_at with DOMAIN and RANGE defined as follow:

DOMAIN	property	RANGE
Event Olympic Games	happened_at	Place Location
Any resource that has given property happened_at is an instance of Event or Olympic Games		The values of a property are instances of one or more classes (for example Place)
Olympic Games Beijing 2022		Beijing
Class	Property	Class

So for instance in an ontology defined in this way when I found the property happened_at from its range I know that its value could be only Place or Location and from its domain, I know that the resource that has this property will be an instance of Event or Olympic Games.

In RDF the property P will have range and domain class C formalized as follow:

P rdfs:range C
P rdfs:domain C

You can read the full definition in the W3C recommendation here.

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