Ontology Alignment

Ontology Alignment , also ontology matching or ontology mapping , describes the finding of correspondences between concepts in ontologies in computer science . Thus the ontology alignment is very similar to the information integration . In the context of the semantic web , ontology matching can help to better network the global knowledge graph and improve the interoperability of web services.

background

In computer science, ontologies are formal, machine-readable descriptions of concepts and their relationships to one another - they standardize the vocabulary that can be used for knowledge representation. In the context of the Semantic Web, knowledge can be represented in a machine-readable manner through the use of ontolgies. For example, a pharmacy could display the opening times on its website using an ontology. A service, such as a search engine, is thus able to "interpret" the opening times and use and present them in a meaningful way for people. Ontology Alignment is necessary when two different ontologies, i.e. two different precabularies, are used to express the same facts. For example, a second pharmacy could announce its opening times using a different ontology. In this case, a web service needs the information that the same facts are displayed both times. The aim of ontology alignment is to determine the relationships between the concepts in mutually different ontologies.

Formal definition

An alignment describes a set of correspondences between two ontologies. In its simplest form, a correspondence is a triple where and represent concepts from two different ontologies and stand for the relation that exists for the two concepts. Values for are, for example, equivalence ( ) or subset ( ). ${\ displaystyle A}$ ${\ displaystyle \ langle e, e ', r \ rangle}$ ${\ displaystyle e}$ ${\ displaystyle e '}$ ${\ displaystyle r}$ ${\ displaystyle r}$ ${\ displaystyle =}$ ${\ displaystyle <}$

The ontology matching process can be formally represented as a function that receives two ontologies and and returns an alignment . Optionally, it also accepts a number of parameters , a number of external resources and an initial alignment . ${\ displaystyle f (o, o ', A, p, r)}$ ${\ displaystyle o}$ ${\ displaystyle o '}$ ${\ displaystyle A '}$ ${\ displaystyle f}$ ${\ displaystyle p}$ ${\ displaystyle r}$ ${\ displaystyle A}$

Methods of ontology alignment

There are now a large number of implemented matching systems which automatically map two ontologies to one another through an alignment. The Ontology Alignment Evaluation Initiative (OAEI) makes data records publicly available, on the basis of which matching systems can be evaluated and compared.

Individual evidence

↑ ^a ^b Jérôme Euzenat, Pavel Shvaiko: Ontology Matching . Springer, New York 2013, ISBN 978-3-642-38720-3 , pp. 41 - 43 .
^ Ontology Alignment Evaluation Initiative (OAEI). Retrieved September 6, 2019 .

[euzenat_shvaiko-1] Jérôme Euzenat, Pavel Shvaiko: Ontology Matching . Springer, New York 2013, ISBN 978-3-642-38720-3 , pp. 41 - 43 .

[2] Ontology Alignment Evaluation Initiative (OAEI). Retrieved September 6, 2019 .