Tate's Subject Hierarchy as a SKOS Taxonomy

This repository features a SKOS taxonomy generated from Tate's subject hierarchy through the use of Catalink's proprietary semantic data integration framework CASPAR.

Scope & Aim

Tate UK has publicly released its subject hierarchy as a set of JSON files organized in three levels. For example, in this artwork by Robert Blake, the relevant subjects are found in section 'Explore'. An excerpt from the list of subjects for the specific artwork is 'religion and belief' > 'universal religious imagery' > 'blessing'. The following table indicates the total number of subjects per level:

Level	Count
level-0	16
level-1	142
level-2	2251

Having the subject hierarchy in SKOS format enables its easy publication and use by third parties as linked data. Thus, in order to establish semantic interoperability with third parties, our aim in this work was to convert the JSON files to a SKOS taxonomy using our in-house CASPAR framework for semantic data integration.

Semantic Data Integration with CASPAR

CASPAR converts the input files into a semantic Knowledge Graph (KG) - in this case an RDF SKOS taxonomy - through the definition of mappings between input data fields and respective ontology concepts. The specification of mappings is compliant with a proprietary Domain-Specific Language (DSL) based on JSON syntax.

Just for reference, the mappings for converting Tate's JSON files into a SKOS taxonomy via CASPAR are found here.

SKOS Taxonomy

The resulting SKOS taxonomy can be found here and its namespace is http://w3id.org/tate-skos#.

Through SKOS Play we generated the subject tree (see figure below), as well as the complete documentation (PDF file), containing the alphabetical index of the subjects with attributes on each entry (notation, broader, narrower, related, all notes), followed by a clickable hierarchical tree that directs to entries in the alphabetical index.

Sample SPARQL Queries

Below is a list of indicative SPARQL queries for retrieving information from the KG.

List All Level-0 Concepts

PREFIX rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#>
PREFIX skos: <http://www.w3.org/2004/02/skos/core#>

SELECT DISTINCT ?level_0_concept
WHERE {
    ?level_0_concept rdf:type skos:Concept .
    MINUS {
        ?other_concept rdf:type skos:Concept .
        ?level_0_concept skos:broader ?other_concept .
    }
} 

List All Level-1 Concepts

PREFIX rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#>
PREFIX skos: <http://www.w3.org/2004/02/skos/core#>

SELECT DISTINCT ?level_1_concept
WHERE {
    ?level_1_concept rdf:type skos:Concept .    
    ?level_1_concept skos:broader ?level_0_concept .
    MINUS {
        ?other_concept rdf:type skos:Concept .
        ?level_0_concept skos:broader ?other_concept .
    }    
} 

List All Level-2 Concepts

PREFIX rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#>
PREFIX skos: <http://www.w3.org/2004/02/skos/core#>

SELECT DISTINCT ?level_2_concept
WHERE { 
	?level_2_concept rdf:type skos:Concept .
    ?level_2_concept skos:broader ?level_1_concept . 
    ?level_1_concept skos:broader ?level_0_concept .
} 

Contact Details

For any queries or remarks on the Tate SKOS taxonomy, or if you would like to deploy CASPAR for your use case, please feel free to contact us.