Ontology & namespaces

The vocabularies used by the PSGC change-history RDF: W3C ORG, PSGC, Dublin Core Terms, PROV, time, and schema.org, and how they combine.

Author

Manuel Balmeo

The PSGC change-history RDF is built on the W3C ORG ontology for organizational structure, with PROV for provenance, Dublin Core Terms for metadata, and per-snapshot PSGC concepts.

Namespaces

Namespaces used across the delta files:

  • org: — W3C ORG (FormalOrganization for Reg/Prov/City/Mun, OrganizationalUnit for Bgy/SubMun)

  • psgc: — the project’s own vocabulary (entity / event / concept URIs — see URIs)

  • dct: — Dublin Core Terms (title, source, legal basis metadata)

  • prov: — PROV-O provenance (linking events to their snapshot and source PSA press release)

  • time: — temporal positioning of effective / plebiscite dates

  • schema: — schema.org supplementary terms

Ontology mapping

PSGC level → ORG class

Each PSGC level is typed as one of two ORG classes (from rdf/builder.py):

PSGC level ORG class Typed as
Region (Reg) org:FormalOrganization autonomous top-level unit
Province (Prov) org:FormalOrganization
Municipality (Mun) org:FormalOrganization
City (City) org:FormalOrganization
Barangay (Bgy) org:OrganizationalUnit sub-unit
Sub-municipality (SubMun) org:OrganizationalUnit sub-unit

A delta only emits the entities touched by that quarter’s changes, so a delta may contain only OrganizationalUnit instances (e.g. the 2023-10-24 delta is all barangays). The --full build emits the entire entity graph with both classes.

Hierarchy

Parent/child relationships are derived from the PSGC code structure and encoded with ORG containment predicates in full builds:

  • org:hasSubOrganization — FormalOrganization → FormalOrganization (e.g. region → province, province → city/municipality).

  • org:hasUnit — FormalOrganization → OrganizationalUnit (e.g. municipality → barangay).

Change events

Each change is an org:ChangeEvent typed via org:classification → a psgc:concept/change-type/{type} concept. The participating entities are attached with org:originalOrganization (the pre-change entity) and org:resultingOrganization (the post-change entity). See Change-event types for the per-type triple shape.

Provenance & metadata

Each change event carries its provenance: dct:source for the legal basis (Republic Act number, Executive Order, plebiscite resolution, etc.), prov:generatedAtTime for the effective date, and dct:description for a human-readable summary of what changed and why.