@prefix owl: . @prefix rdfs: . @prefix dc: . @prefix foaf: . @prefix xsd: . @prefix qb: . @prefix prov: . @prefix rdf: . a owl:Ontology, ; rdfs:label "Dataset Quality Vocabulary (daQ)" ; rdfs:comment "The Dataset Quality Vocabulary (daQ) is a lightweight, extensible core vocabulary for attaching the result of quality benchmarking of a linked open dataset (usually an expensive process) to that dataset. daQ is designed to be extended by custom quality metrics. Use cases include filtering and ranking datasets by quality." ; dc:creator [ foaf:name "Jeremy Debattista" ; foaf:homepage ; foaf:mbox ], [ foaf:name "Christoph Lange" ; rdfs:seeAlso ; foaf:homepage ] ; dc:modified "2015-04-01"^^xsd:date . a qb:DataStructureDefinition ; qb:component [ qb:dimension ; qb:order 1 ], [ qb:dimension ; qb:order 2 ], [ qb:dimension ; qb:order 3 ], [ qb:measure ], [ qb:attribute ; qb:componentRequired true ; qb:componentAttachment qb:DataSet ] . a rdfs:Class, owl:Class ; rdfs:subClassOf , qb:DataSet, [ a owl:Restriction ; owl:onProperty qb:structure ; owl:hasValue ] ; rdfs:comment "Defines a quality graph which will contain all metadata about quality metrics on the dataset." ; rdfs:label "Quality Graph Statistics" . a rdfs:Class, owl:Class ; rdfs:subClassOf prov:Entity, qb:Observation ; rdfs:comment "A quality observation represents the statistical and provenance information of the attached metric's assessment activity." ; rdfs:label "Quality Observation" . a rdfs:Class, owl:Class ; rdfs:comment "The highest level of quality metric is a category. A category groups a number of dimensions relevant to each other which aims at measuring the quality of a dataset from different aspects. Categories are provided as subclasses of this abstract class, which is not intended for direct usage." ; rdfs:label "Category" . a rdfs:Class, owl:Class ; rdfs:comment "Each dimension is part of a larger group called category (See daq:Category). Each dimension has a number of metrics which are associated to it. A dimension is linked with a category using the daq:hasDimension property. Dimensions are provided as subclasses of this abstract class, which is not intended for direct usage." ; rdfs:label "Dimension" . a rdfs:Class, owl:Class ; rdfs:comment """The smallest unit of measuring a quality dimension is a metric. A metric belongs to exactly one dimension. Each metric has one or more observations ( exttt{daq:hasObservation}), which records data quality assessment value following a computation. Metrics are provided as subclasses of this abstract class, which is not intended for direct usage.""" ; rdfs:label "Metric" . a rdf:Property, owl:ObjectProperty, qb:DimensionProperty ; rdfs:label "computed by" ; rdfs:comment "TODO: Define properly" ; rdfs:domain qb:Observation . a rdf:Property, owl:ObjectProperty, qb:DimensionProperty ; rdfs:label "computed on" ; rdfs:comment "Quality metrics can be (in principle) calculated on various forms of data (such as datasets, graphs, set of triples etc...). This vocabulary allow the owner/user of such RDF data to calculate metrics on multiple (and different) resources." ; rdfs:domain qb:Observation ; rdfs:range rdfs:Resource . rdfs:domain qb:Observation ; rdfs:range xsd:dateTime ; owl:cardinality "1"^^xsd:nonNegativeInteger . a rdf:Property, owl:DatatypeProperty ; rdfs:label "has observation" ; rdfs:comment "Computed metrics can have 1 or more quality observations, where each computed resource has one observation." ; rdfs:domain ; rdfs:range ; owl:minCardinality "1"^^xsd:nonNegativeInteger ; owl:inverseOf . a rdf:Property, owl:DatatypeProperty, qb:DimensionProperty ; rdfs:label "metric" ; rdfs:comment "Represents the metric being observed." ; rdfs:domain qb:Observation ; rdfs:range ; owl:minCardinality "1"^^xsd:nonNegativeInteger ; owl:inverseOf . a rdf:Property, owl:DatatypeProperty, qb:MeasureProperty ; rdfs:label "value" ; rdfs:comment "Each metric will have a value computed. In order to deal with the different return type of the metric computation, this property links a metric with a value object (e.g. boolean, double, Literal)." ; rdfs:domain qb:Observation ; owl:cardinality "1"^^xsd:nonNegativeInteger . a rdf:Property, owl:DatatypeProperty ; rdfs:label "expected data type" ; rdfs:comment "Each metric should have an expect data type for it's observed value (e.g. xsd:boolean, xsd:double etc...)" ; rdfs:domain ; rdfs:range xsd:anySimpleType ; owl:cardinality "1"^^xsd:nonNegativeInteger . a rdf:Property, owl:ObjectProperty ; rdfs:label "requires" ; rdfs:comment "A metric might require a number of external resources (e.g. a gold standard) in order to be able to measure the quality. In order to cater for the most generic requirement, this property links a metric to the required resource (e.g. a URI to the gold standard dataset used)." ; rdfs:domain ; rdfs:range rdfs:Resource . a rdf:Property, owl:ObjectProperty ; rdfs:label "is estimate" ; rdfs:comment "This property flags true if an assessed observation of a metric gives an estimate result instead of a more accurate one." ; rdfs:domain qb:Observation ; rdfs:range xsd:boolean ; owl:cardinality "1"^^xsd:nonNegativeInteger . a rdf:Property, owl:ObjectProperty ; rdfs:label "hasDimension" ; rdfs:comment "The category concept classifies dimensions related to the measurement of quality for a specific criteria. This is an abstract property and should not be used directly. Specific sub-properties should be inherited for different dimensions." ; rdfs:domain ; rdfs:range . a rdf:Property, owl:ObjectProperty ; rdfs:label "hasMetric" ; rdfs:comment "A dimension is an abstract concept which groups an number of more concrete metrics to measure quality of a dataset. This is an abstract property and should not be used directly. Specific sub-properties should be inherited for different metrics." ; rdfs:domain ; rdfs:range .