Previous topic  Top  Next topic  Print this Topic
 

Inferencing

 

OntoBroker RDF supports a configurable sub-set of RDF/RDFS inferencing. As default a sub-set is choosen to achieve good performance. This includes these RDFS rules

RDFS2: RDF.Entailment.Domain
RDFS3: RDF.Entailment.Range
RDFS5: RDF.Entailment.PropertyTransitivity
RDFS7: RDF.Entailment.PropertyInheritance
RDFS9: RDF.Entailment.ClassInheritance
RDFS11: RDF.Entailment.ClassTransitivity
RDF.PropertyDef.ByHierarchy
RDF.ClassDef.ByHierarchy

in which the last two rules implement a sub-set of the axiomatic facts covered by the internal concept/property hierarchy. If more detailed control is required inferencing using the hierarchies could be disabled and selectively (additional) rules switched on/off. Simply activate the configuration settings

RDF.Infer.Properties = on

RDF.Infer.Classes = on

and the additional rules

RDF1: RDF.PropertyDef.ByPredicate
RDF.PropertyDef.ByDomain
RDF.PropertyDef.ByRange
RDF.PropertyDef.BySubpropertySubject
RDF.PropertyDef.BySubpropertyObject
RDF.ClassDef.ByType
RDF.ClassDef.ByDomain
RDF.ClassDef.ByRange
RDF.ClassDef.BySubclassSubject
RDF.ClassDef.BySubclassObject

can be used instead of the internal hierarchies.

Finally some internal rules are used to mediate between asserted and inferred facts.

RDF.Helper.Subclass
RDF.Helper.Subproperty
RDF.Helper.TypeTemp
RDF.Helper.Type

All given rules can be incrementally materialized by setting the option "Materialization.<identifier>" to "on", e.g.

Materialization.RDF.Entailment.ClassTransitivity = on