has_subject association has subject Propositional statements can be represented in RDF as directional subject-predicate-object (S-P-O) triples. RDF reification vocabularies such as OBAN create named individuals in a graph that represent such S-P-O propositional statements. In OBAN, these are called 'associations', and the semantics of these associations can be represented using properties that link it to the subject, predicate, and object of the triple it represents. This property is defined by OBAN to specifically link 'associations', which are proposition-level entities, to their subject (sensu RDF). It is therefore a more specific relation than its has_subject parent, which can be used to link a statement or proposition to its subject. association