Ontologies which are built with the RDF framework consist of concepts and relationship between these concepts.
Additionally several restrictions in the form of axioms can be defined, using terms of the RDFS and OWL vocabulary.
To understand how current ontologies are modeled we created Montolo.
MontoloVoc is an OWL and RDFS-based vocabulary initially describing concepts regarding restrictions, and it is RDF Data Cube-based so that statistics regarding restrictions can be described.
The restriction concepts entail abstract Restriction Types, such as disjoint classes or reflexive properties,
and different restriction type Expressions for each type, e.g.
owl:AllDisjointClasses for the restriction type disjoint classes.
Information regarding the use of restriction types are published as MontoloStats dataset, described using the MontoloVoc vocabulary and currently covering 660 ontologies (98%) of LOV and 565 ontologies of BioPortal.
The dataset is available on this website, but also on Zenodo under a CC0 license.
Montolo provides following resources:
The latest MontoloStats dataset gives us following analytics: