FAIR² Ontology

Overview

The FAIR² Ontology defines the core semantic entities and relations used across FAIR² metadata and datasets. It provides a structured, machine-readable vocabulary that ensures interoperability between data, methods, and publications within the FAIR² ecosystem. The ontology reuses existing standards from Schema.org, PROV-O, and the Contributor Role Ontology (CRO), while extending them with specific terms for AI-ready data curation and Responsible AI alignment.

The ontology is expressed in both JSON-LD and Turtle formats and is compatible with SHACL validation shapes defined under the fair2s: namespace.

Namespaces

Prefix	Namespace URI
`schema:`	https://schema.org/
`prov:`	http://www.w3.org/ns/prov#
`cr:`	https://credit.niso.org/contributor-roles/
`fair2:`	https://fair2.ai/ns/
`fair2s:`	https://fair2.ai/shapes/
`rdfs:`	http://www.w3.org/2000/01/rdf-schema#
`rdf:`	http://www.w3.org/1999/02/22-rdf-syntax-ns#
`xsd:`	http://www.w3.org/2001/XMLSchema#

Classes

The following classes define the core conceptual entities in FAIR². Each class extends a compatible Schema.org or PROV-O superclass to ensure semantic interoperability.

`@id`	`rdfs:label`	`rdfs:comment`	`rdfs:subClassOf`
`fair2:DataArticle`	DataArticle	Scholarly article describing and linking an open dataset with methods and reuse guidance.	`schema:ScholarlyArticle`
`fair2:OpenDataArticle`	OpenDataArticle	Legacy alias for `fair2:DataArticle`; retained for backward compatibility.	`schema:ScholarlyArticle`
`fair2:DataPortal`	DataPortal	An online portal or platform that hosts and serves the dataset.	`schema:CreativeWork`
`fair2:DataArchive`	DataArchive	A long-term archive or repository that preserves the dataset.	`schema:CreativeWork`
`fair2:Section`	Section	Structured methodology section grouping procedural steps.	`schema:HowToSection`
`fair2:MethodSection`	MethodSection	Legacy alias for `fair2:Section`; retained for backward compatibility.	`schema:HowToSection`
`fair2:Step`	Step	Atomic procedural instruction within a method.	`schema:HowToStep`
`fair2:Substep`	Substep	Subordinate procedural instruction nested under a Step.	`schema:HowToStep`
`fair2:AuthorRole`	AuthorRole	Role played by an author in producing the dataset (e.g. Corresponding Author).	`schema:Role`
`fair2:ContributorRole`	ContributorRole	Contributor role drawn from CRediT/CRO vocabularies.	`schema:Role`
`fair2:RecordSet`	RecordSet	A coherent subset of a dataset used for analysis or curation.	`schema:Dataset`
`fair2:Visualization`	Visualization	A visual artifact (plot, figure, dashboard) derived from the dataset.	`schema:CreativeWork`
`fair2:DescriptiveStatistics`	DescriptiveStatistics	Summary statistics computed over a RecordSet or Dataset.	`schema:Dataset`
`fair2:Submission`	Submission	Submission package that groups dataset, article, and supporting materials for review.	`schema:CreativeWork`

Properties

The FAIR² properties define relationships between datasets, methods, contributors, and derived artifacts. They support semantic traceability and alignment with FAIR data and Responsible AI requirements.

`@id`	`rdfs:label`	`rdfs:comment`
`fair2:activities`	activities	Groups workflow or provenance activities related to an entity.
`fair2:attachment`	attachment	Points to a supporting file or supplemental material.
`fair2:builds`	builds	Indicates that one artifact is built from or extends another artifact.
`fair2:bugFixes`	bugFixes	Bug-fix entries within a changelog update description.
`fair2:citationKey`	citationKey	Short citation key identifying the dataset.
`fair2:contributorRole`	contributorRole	Links a contribution to a contributor role term.
`fair2:dataArchive`	dataArchive	Links a dataset to the archive that preserves it.
`fair2:dataArticle`	dataArticle	Links a dataset or submission to its associated scholarly data article.
`fair2:dataPortal`	dataPortal	Links a dataset to the portal that hosts and serves it.
`fair2:dataset`	dataset	References the dataset resource associated with the entity.
`fair2:digest`	digest	Provides a short textual or hash-based digest for quick identification.
`fair2:domain`	domain	Subject-domain classification of the dataset (e.g. a Wikidata concept).
`fair2:generated`	generated	Links a method step to the RecordSet fields or artifacts it produced (lineage).
`fair2:improvements`	improvements	Improvement entries within a changelog update description.
`fair2:isExperimentRelated`	isExperimentRelated	Flags whether a field relates to experimental data.
`fair2:manuscript`	manuscript	References a manuscript file associated with the submission.
`fair2:methodSection`	methodSection	Links a dataset to its methodology section(s).
`fair2:newFeatures`	newFeatures	New-feature entries within a changelog update description.
`fair2:next`	next	Orders sequential method sections, steps, or substeps.
`fair2:nextTrue`	nextTrue	Conditional branch target taken when a StepCase condition holds.
`fair2:otherInformation`	otherInformation	Miscellaneous notes within a changelog update description.
`fair2:qualifiedUsage`	qualifiedUsage	Condition guarding a conditional method step (StepCase).
`fair2:roleName`	roleName	Human-readable label for a contributor role.
`fair2:statistics`	statistics	Links to computed descriptive statistics.
`fair2:step`	step	Connects a Section with its constituent Step items.
`fair2:store`	store	Indicates the storage location or repository endpoint for an asset.
`fair2:substep`	substep	Connects a Step with its constituent Substep items.
`fair2:unit`	unit	Unit of measurement for a field or variable.
`fair2:variables`	variables	Lists variable or feature definitions referenced by an analysis or record set.
`fair2:visualization`	visualization	Links to a visualization derived from the dataset or record set.

Notes

Each property and class is compatible with JSON-LD serialization and SHACL validation.
The fair2s: namespace hosts corresponding SHACL shape definitions for data validation.
The ontology is designed for seamless integration with ML Schema, Croissant, and PROV-O provenance structures.