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For detailed information about the browse visualisation, please see the Browse visualisation guide for publishers.

Many of the vocabularies published at Research Vocabularies Australia have associated vocabulary data that has been imported into the vocabulary repository. If this vocabulary data is defined using SKOS, the portal will provide a simple browse function directly within the vocabulary's portal page. Depending on the configuration options set at the time of publication in RVA, the browse function may display additional nodes for SKOS concept schemes and SKOS collections.

The browse function provides a tree-like display of the concepts, arranging them by broader/narrower relationships. Here is an example vocabulary page that shows the portal's concept browsing function:

The portal browse function is provided for vocabularies which meet the following requirements:

  • Vocabulary data has been uploaded into the repository, either as a file upload, or by importing from PoolParty.
  • If the vocabulary was uploaded as a file upload:
    • The vocabulary data was uploaded as RDF.
    • The vocabulary defines concepts as SKOS Concepts.
  • The vocabulary is tree-structured: there are no cycles in the broader/narrower relationships.
    • However, polyhierarchies are supported: each instance of a concept is shown in the places it occurs in the broader/narrower hierarchy.

I published a vocabulary, but portal concept browsing is not shown ...

If you've published a vocabulary, and you expect to see portal concept browsing, but do not, here is a checklist of questions to consider.

  • Did you add a version, and import vocabulary data, either from PoolParty, or as a file upload?
  • For a file upload:
    • Did you upload vocabulary data in an RDF format?
    • Does your vocabulary data define concepts using SKOS?
  • Does your vocabulary have a cycle in the broader/narrower relationships? If so, the portal is unable to offer concept browsing. In this case, please consider adding the top concepts manually using the "Top Concepts" section of the portal metadata editor.

I published a vocabulary, but the broader/narrower relationships aren't displayed correctly

If you've published a vocabulary, but concepts that are related in the SKOS broader/narrower hierarchy aren't being displayed as parent/child nodes, it's likely because of some combination of the version settings you've made in RVA, and certain triples missing from your vocabulary data. Here's what to look for.

  • When you created the version in RVA, did you select the setting "Display SKOS Concept Schemes"? If so, please note that with this setting enabled, the browse visualisation strictly respects the semantics of SKOS concept schemes and the broader/narrower hierarchy. See the next section.
  • If you didn't select the setting "Display SKOS Concept Schemes" setting, the parent/child relationship of concepts shown in the browse visualisation corresponds only to the SKOS broader/narrower relations; it ignores membership of concept schemes, including the indication of top concepts. In this case, the concepts shown at the top level are those concepts that have no broader concepts. If the display seems to be incorrect, please double-check your vocabulary data.

How the visualisation works when "Display SKOS Concept Schemes" is set

As noted above, if this setting is enabled, the semantics of SKOS concept schemes and the broader/narrower hierarchy is respected. This means:

  • The browse visualisation will show a top-level node for each concept scheme.
  • Every concept that belongs to a concept scheme will be shown somewhere as a child/descendant of the corresponding concept scheme. If a concept belongs to more than one concept scheme, it is shown as a descendant of every such concept scheme.
  • The direct children of a concept scheme node are:
    • the top concepts of the concept scheme;
    • other concepts that belong to the concept scheme, which are not reachable in the broader/narrower hierarchy from any of the concept scheme's top concepts, and which have no broader concepts. This is why it's possible to see below a concept scheme node some concepts with the "T" icon and some without it.
  • Every concept that doesn't belong to any concept scheme will be shown either at the top level of the browse visualisation, or as a child/descendant of such a top-level concept, based on the SKOS broader/narrower hierarchy.

Therefore, if you see some concepts displayed at the top level that you believe should be displayed as child/descendant nodes of a concept scheme, then the skos:inScheme RDF triples are missing for those concepts.

The key thing to know is that membership of concept schemes does not automatically follow the SKOS broader/narrower hierarchy. Just because a concept B is marked as narrower than a concept scheme's top concept A, does not by itself mean that B is also a member of the concept scheme. If you want B also to be a member of the concept scheme, this membership must be explicitly asserted using an RDF triple in the vocabulary data. This is explained in Section 4.6.4, "Scheme Containment and Semantic Relations", of the SKOS Reference.

At this point, the following question arises:

  • Did you create this vocabulary in PoolParty?
    • If so, then you've probably encountered a significant known "gotcha" with the default behaviour of PoolParty.
    • By default, when you create a concept scheme and populate it using the PoolParty user interface, concepts are not marked using the skos:inScheme property. The consequence of this is that only the top concepts are marked as belonging to the containing concept scheme (i.e., using the skos:topConceptOf and skos:hasTopConcept properties.).
    • To make the vocabulary data consistent with the way that PoolParty displays it, you need to activate some additional settings in the PoolParty project.
    • To do this, open the project in PoolParty, use the "Advanced" menu to select "In Scheme Settings" → "Enable In Scheme". Then, again in the "Advanced" menu, turn on "In Scheme Settings" → "Add In Scheme Relations to All Concepts", and also enable "Add In Scheme Relations On Concept Creation" and "Update In Scheme Relations On Concept Changes".
    • Unfortunately, these settings are per-project, not per-user; you need to do this separately for each of your PoolParty projects.
  • If you created the RDF vocabulary data outside PoolParty, you'll need to review your vocabulary data, and manually add a triple my:C skos:inScheme my:CS for each concept my:C you want to be in the concept scheme my:CS that isn't a top concept of my:CS.


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