The Semantic Puzzle

Florian Huber

Transforming music data into a PoolParty project

Goal

For the Nolde project it was requested to build a knowledge graph, containing detailed information about the austrian music scene: artists, bands and their music releases. We decided to use PoolPartyWeb based ontology manager which can serve as a central hub for your knowledge organization. With PoolParty you can organize and maintain knowledge models based on widely accepted specifications like RDF, SPARQL and SKOS., since theses entities should be accessible in an editorial workflow. More details about the implementation will be provided in a later blog post.

In the first round I want to share my experiences with the mapping of music data into SKOSSimple Knowledge Organization System (SKOS) is a family of formal languages designed for representation of thesauri, classification schemes, taxonomies, subject-heading systems, or any other type of structured controlled vocabulary. SKOS is built upon RDF and RDFS, and its main objective is to .... Obviously, LinkedBrainz was the perfect source to collect and transform such data since this is available as RDF/NTriples dumps and even providing a SPARQL endpoint! LinkedBrainz data is modeled using the Music OntologyProvides main concepts and properties fo describing music (i.e. artists, albums, tracks, but also performances, arrangements, etc.). (http://musicontology.com/).

E.g. you can select all mo:MusicArtists with relation to Austria.

SELECT query

I imported LinkedBrainz dump files and imported them into a triple store, together with DBpediaDBpedia is a project aiming to extract structured information from the information created as part of the Wikipedia project. This structured information is then made available on the World Wide Web. DBpedia allows users to query relationships and properties associated with Wikipedia resources, ... dumps.

With two CONSTRUCTThe open semantic framework (OSF) uses the Drupal CMS via the conStruct plug-in modules. conStruct is a distro of the Drupal framework specifically developed to provide management, access and visualization of structured content. (http://openstructs.org/conStruct/) queries, I was able to collect the required data and transform it into SKOS, into a PoolParty compatible format:

Construct Artists

CONSTRUCT Artists#1

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Every matching MusicArtist results in a SKOS concept. The foaf:name is mapped to skos:prefLabel (in German).

As you can see, I used Custom Schema features to provide self-describing metadata on top of pure SKOS features: a MusicBrainzMusicBrainz is a project that aims to create an open content music database. Similar to the freedb project, it was founded in response to the restrictions placed on the CDDB. However, MusicBrainz has expanded its goals to reach beyond a compact disc metadata storehouse to become a structured ... link, a MusicBrainz Id, DBpedia link, homepage…

In addition you can see in the query that also data from DBpedia was collected. In case a owl:sameAsService that helps to find co-references between different data sets. (http://sameas.org) relationship to DBpedia exists, a possible abstract is retrieved. When a DBpedia abstract is available it is mapped to skos:definition.

Construct Releases (mo:SignalGroups) with relations to Artists

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Similar to the Artists, a matching SignalGroup results in a SKOS Concept. A skos:related relationship is defined between an Artist and his Releases.

Outcome

The SPARQL construct queries provided ttl files that could by imported directly into PoolParty, resulting in a project, containing nearly 1,000 Artists and 10,000 Releases:

PoolParty thesaurus

 

You can reach the knowledge graphIn mathematics, a graph is an abstract representation of a set of objects where some pairs of the objects are connected by links. The interconnected objects are represented by mathematical abstractions called vertices, and the links that connect some pairs of vertices are called edges. ... by visting the publicly available Linked Data Frontend of PoolParty: http://nolde.poolparty.biz/AustrianMusicGraph

E.g. you can find out details and links about Peter Alexander or Conchita Wurst.