Glossary
Bounded Federation
Assertion
A semantic statement concerning a subject, predicate, and value. In the present framework, the elementary assertion is represented as the ordered tuple \((s,p,v)\). Where represented in RDF, this structure corresponds to the subject–predicate–object structure of an RDF triple.
Atomic assertion
An assertion treated as a single independently identifiable and reviewable semantic unit, represented as \((s,p,v)\), where \(s\) is the subject, \(p\) the predicate, and \(v\) the value. Atomic indicates that the assertion is not decomposed into simpler assertions within the operation under consideration.
Bounded federation
Purpose-directed and reviewable semantic exchange between independently governed knowledge graphs within an explicitly delimited federation boundary. Bounded federation establishes the semantic warrant for specified assertion-level exchanges without asserting global equivalence between the participating ontologies or knowledge graphs. Its distinctive boundary is therefore semantic and operational: other federation architectures may independently restrict technical reachability, query relevance, access, or participation.
Bounded projection
A relational projection restricted to the subjects, predicates, assertions, or other semantic elements selected for a federation boundary. A bounded projection exposes the candidate space required for a specified federation operation rather than projecting the source knowledge graph as a whole. The projection changes how candidate assertions are arranged and presented for review without changing their semantic identity or candidate status.
Candidate assertion
An assertion made available for consideration but not thereby assumed to be corroborated, stabilised, or warranted for federation.
Competence
The capacity to responsibly perform a specified knowledge-producing or semantic operation. In bounded federation, competence is a relational property of a specified federation operation: it concerns what may be interpreted, exchanged, or supported for a declared purpose, between specified participating semantic systems, in a specified direction, under the relevant semantic patterns and provenance conditions. Competence is therefore not an intrinsic ranking or general property of a knowledge graph. Establishing competence for one class of exchange does not establish competence for assertions or inferences outside that boundary.
Competency question
A question used to state what an ontology, ontological pattern, or bounded federation is intended to be capable of representing or answering. In bounded federation, competency questions operationalise the pragmatic purpose of an exchange and contribute to delimiting its federation boundary (Blomqvist et al. 2016).
European Interoperability Framework (EIF) The European Interoperability Framework (EIF) is a set of recommendations and guidelines that aims to facilitate communication and collaboration between public administrations, businesses, and citizens within the European Union and across national borders (Commission and Digital Services 2017).
Federation boundary
The explicitly delimited semantic domain within which a federation claims sufficient competence for specified exchanges. A federation boundary may restrict participating entities, predicates, ontological patterns, candidate assertions, directions of exchange, or other conditions relevant to the federation. Assertions outside the boundary are not thereby considered false or invalid; no federation claim is made about them.
Federation outcome
The federation-specific result associated with a reviewed candidate correspondence or exposed subject–predicate intersection. The present demonstrator distinguishes Federate, Redefine, Skip, and Not applicable. These outcomes describe different relationships to the proposed federation operation and do not constitute either a truth scale or a replacement for the underlying review state.
Federate
A federation outcome indicating that a candidate assertion or correspondence is sufficiently established for the specified exchange within the declared federation boundary. Federation does not imply global equivalence between the participating graphs, entities, predicates, or ontologies.
Inferential competence
The bounded competence of a federation to support specified interpretations or inferences involving federated assertions. Warrant to exchange an assertion does not by itself establish warrant for every inference that the destination graph can derive from that assertion.
Intermediate semantic representation
A semantically explicit computational representation constructed for a particular operation of semantic knowledge production or mediation. It preserves the identities and semantic roles required to reconstruct the underlying assertions and their provenance. In bounded federation, the atomic tuple \((s,p,v)\) provides an intermediate semantic representation through which assertions originating in one graph can be reviewed for use in another without becoming the persistent ontology of either graph.
Knowledge graph
A knowledge representation that uses a graph-structured data model to represent and operate on data (ISO 2023).
Not applicable
A federation outcome indicating that an exposed subject–predicate intersection does not constitute a candidate assertion within the federation boundary. Not applicable is distinct from an unknown or missing value, rejection, deferral, and Skip: no atomic candidate assertion exists at that intersection.
Ontological pattern
A reusable semantic structure addressing a recurring modelling problem. In bounded federation, an ontological pattern identifies the portion of semantic structure required to support the declared competency questions without requiring complete alignment of the participating ontologies (Blomqvist et al. 2016; Berardinis et al. 2023).
Pragmatic purpose
The declared purpose for which a bounded federation is established. The pragmatic purpose motivates competency questions against which the adequacy of the federation can be assessed. Pragmatic does not mean approximately correct or merely convenient: correspondence must be adequate for the declared purpose under explicit competence boundaries.
Provenance
Information describing the entities, activities, and agents involved in producing, influencing, or delivering data or another thing, including relevant relations of use, generation, derivation, association, attribution, and responsibility (Moreau and Missier 2013; Lebo et al. 2013). In bounded federation, provenance permits reviewed correspondences and federation outcomes to remain attributable to the activities through which they were established.
Reconciliation
A knowledge-producing activity that proposes or establishes relationships between locally represented entities or expressions and entities or identifiers in external knowledge representations, authority systems, registers, or other namespaces. Reconciliation may establish corresponding entities without establishing that every assertion concerning those entities can be federated.
Redefine
A federation outcome indicating that sufficient semantic contact exists to identify a related commitment, but the proposed correspondence does not adequately preserve the meaning required by the destination graph. The appropriate local formulation is retained or established rather than treating the source and destination representations as semantically interchangeable.
Relational projection
An operational construct or view that maps underlying semantic assertions into a specified tabular or relational structure for computational processing (ISO 2023; ISO/IEC 2024). A relational projection may select, join, or reshape assertions without altering the identities of the underlying atomic assertions.
Review
The Review Algebra operation through which an existing candidate assertion, or one or more of its components, is examined and a semantic value together with an explicit review status is returned (Antal 2026). Review records a qualified, provenance-bearing judgement rather than establishing truth: reviewers remain fallible, and review outcomes may therefore be revised or differ between review activities (Li et al. 2019). In bounded federation, review determines whether proposed semantic exchanges are warranted for the declared federation operation.
Scope
An explicit qualification of the semantic or applicability context within which an assertion is intended to hold. Scope may contribute to determining whether an assertion or operation falls within a federation boundary but is not synonymous with that boundary.
Semantic mediation representation
An intermediate semantic representation used to mediate between independently represented semantic systems. In the present model, the atomic tuple \((s,p,v)\) provides a thin common representation in which graph-to-graph candidate correspondences can be made explicit and reviewed without replacing the persistent representation of either participating graph.
Skip
A federation outcome indicating that a candidate assertion exists but its exchange is not warranted in the current federation operation. Skip therefore differs from Not applicable, where no candidate assertion exists at the exposed subject–predicate intersection.
Tuple
An ordered collection of values, fields, or elements (ISO/IEC 2024). In the present framework, the atomic assertion \((s,p,v)\) is represented as a three-field tuple whose positions have explicitly defined semantic roles.
Warranted exchange
A semantic exchange admitted through review and finalisation as adequate for the declared federation purpose and competence boundary. Warrant for an exchange is bounded and does not by itself imply global semantic equivalence, unrestricted inferential warrant, destination-graph admission, or normative authority.
Wide projection
A relational projection in which assertions sharing a subject are reshaped so that selected predicates become columns where cardinalities permit an unambiguous pivot. In bounded federation, a wide projection may expose a rectangular subject–predicate space containing intersections that do not correspond to candidate assertions; these can be represented explicitly as Not applicable.
Domain Glossaries
asset identifier: persistent identifier used for musical works, sound recordings, editions, audiovisual items, or other cultural objects. CITF requires asset identifiers to be resolvable and interoperable across systems. (citf_2025?)
Music terms
audio recording: fixation of sounds (ISO 2019)
creator: in the context of this policy paper, we use the broad term for the arranger, author, composer, lyricist; for individual definitions see ISWC standard (ISO 2022)
DSP or digital streaming platform: Digital service providers (DSPs), or Digital Streaming Platforms are companies or organisations that provide access to services online. DSPs can provide access to music downloads, like Apple’s iTunes Store, or access to streaming music like Spotify, or even provide satellite-delivered content such as SiriusXM in the USA.
expression: intellectual or artistic realisation of one and only one work
Note: may take the form of a notation
manifestation: physical embodiment of an expression (ISO 2017)
movement: A principal division of a musical work. (ISO 2022)
music video recording: fixation of sounds synchronized with pictures or moving pictures where (a) the fixed sounds are wholly or substantially a musical performance or (b) the recording is intended for viewing in association with a recording of a musical performance. This definition includes music videos and concert recordings, together with music-related interviews and documentaries, but does not extend to genera! audiovisual material, even if it includes music.(ISO 2019)
musical work: composed of a combination of sounds, with or without accompanying text (ISO 2022)
original title: A title given to the work by its creator(s) shown in its original language. (ISO 2022)
formal title: A standardized title in which the elements are arranged in a pre-determined order, such as titles created for classical works. (ISO 2022)
ISMN: The International standard music number (ISMN) was developed by, and for, the music publishing sector as a separate system to complement the International standard book number (ISBN). The existence of the ISMN as a separate identifier system makes it possible to identify printed and notated music as a distinct category of publication within the global supply chain and to develop trade directories and similar services for the specialized market for music publications. (→ asset identifier)
rights management (organisations): the function of managing the rights on behalf of rights owners. It can be companies whose sole purpose is to ensure that content that has been licensed has delivered royalties that are identified and accounted for. The role can be taken by collective management organisations or by private companies on behalf of songwriters, composers, performers, music publishers, or record labels.
original version: The first established form of a work. (ISO 2022)
performer: The performer of a musical work; in case of a sound recording, the performer whose performance is fixed in the recording. They may be entitled to neighbouring rights in sound recordings. In some contexts, the performer is part of the broadly defined creator group.
producer: The person or legal entity that produces the recorded fixation of the sound recording. They are entitled to neighbouring or sound recording copyrights. In some contexts, the producer is part of the broadly defined creator group.
track: single recording on a sound carrier (ISO 2017)
work: distinct, abstract creation of the mind whose existence is revealed through one or more expressions (e.g. a performance) or manifestations (e.g. an object) (ISO 2022)