DCMI 2025: Using Schema and Value Vocabularies to Provide Consistency Across Structured Content

Panel Description

Application profiles provide a framework for structuring information related to a particular application. These can include two types of vocabularies – schema and value vocabularies. Schema vocabularies specify the properties and attributes related to the application, while value vocabularies specify the valid instances for those properties and attributes.

Schema vocabularies can point to existing schemas such as SKOS (Simple Knowledge organization Scheme), RDFS (RDF Schema), Dublin Core, FOAF (Friend of a Friend), Schema.org, etc. They can also be specialized to add combinations of properties and attributes from multiple existing schemas or localized to add custom properties and attributes. Schema vocabularies are crucial for interoperability of applications when querying federated resources, aggregating disparate resources into a common resource such as a data warehouse or data lakehouse, or conducting transactions with an external application.

Value vocabularies can be simple controlled vocabularies, or taxonomies, ontologies, or other types of terminologies. Value vocabularies are crucial for consistency, discoverability, and reusability. Whether tagging, filtering, or defining relationships between concepts, value vocabularies bring clarity and reduce ambiguity.

This panel discussed the interplay between schema vocabularies that structure content with value vocabularies that provide consistency across structured content, and particularly how automation can optimize the linked data ecosystem. Panelists provided a 5-minute overview of their background and interest in schema and value vocabularies, then the panel discussed the following questions:

  • Why do application profiles primarily focus on schema vocabularies and not on value vocabularies?
  • What are the greatest challenges in getting agreement on what value vocabularies to include in an application profile?
  • Are domain use cases sufficiently specified in application profiles?
  • What are the technical challenges and solutions in structuring content to comply with application profiles like DITA (Darwin Information Typing Architecture), DCAT (Data Catalog Vocabulary), and iiRDS (intelligent information Request and Delivery Standard)?
  • What are the differences and similarities between Dublin Core applications profiles, iiRDS, and DITA?

Date: October 23, 2025

Venue: University of Barcelona, Spain

Location:Barcelona, Spain

Broad Topic: Information Architecture

Moderator: Joseph Busch, Principal Analyst, Taxonomy Strategies

Presenters:

  • Heather Hedden
  • Lief Erickson
  • Noz Urbina
  • Peter Winstanley

Watch Moderators Introduction

Download Presentation | PDF

Presentation Script

Download Script | PDF

[Slide 1] Panel: Schema and Value Vocabularies for Consistency

Using Schema and Value Vocabularies to Provide Consistency Across Structured Content

Dublin Core Metadata Applications conference on October 23, 2025 at 2:30-4:30 PM

[Slide 2] I will be your moderator today. I’m Joseph Busch, the founder and principal analyst at Taxonomy Strategies and have been a long-time participant in the Dublin Core Metadata Initiative (DCMI). 

We’re very fortunate to have an amazing panel for this discussion including:

  • Heather Hedden, a taxonomy consultant who has worked in information management for 30 years, initially with the library vendor Gale. She has also been employed as a taxonomist at companies including Cengage, Semantic Web Company, and Enterprise Knowledge. Currently she is improving the taxonomies for Northern Light, a competitive intelligence vendor. 
  • Lief Erickson, a content strategy consultant for businesses with outdated technical documentation practices. He helps organizations modernize their content strategy so they can focus on their next innovation. He has expertise in metadata, search optimization, and content operations (ContentOps).
  • Noz Urbano, a leader in content strategy and user experience. He’s a pioneer in audience journey mapping and adaptive content modelling for delivering personalized, omnichannel experiences. His clients include Pfizer, Moderna, Microsoft, IKEA, Eli Lilly, Mastercard, Barclays Bank, amd National Geographic Society.
  • Peter Winstanley, an ontologist on the Semantic Arts team. He was an editor of the W3C “Data Catalog” vocabulary recommendation. A former interoperability specialist with the UK Government Linked Data and Data Architects’ Working Groups and the European Commission “Joinup” and SEMIC semantic technologies community. He is currently co-Chair of the W3C Dataset Exchange Working Group.

[Slide 3] An application profile defines a specific set of requirements, settings, and metadata for a particular application to ensure compatibility and functionality

[Slide 4] The profile adapts general standards or frameworks to meet the needs of a specific use case, for example, using Dublin Core for bibliographic description and FOAF for named entity properties rather than specifying a whole schema from scratch.

[Slide 5] In the context of application profiles, there are two kinds of vocabularies – concept schemes (like metadata schemas) and semantic schemes (which are controlled vocabularies, including taxonomies, thesauri, and ontologies). Concept schemes structure the how of information, defining the elements and rules for metadata, while semantic schemes, such as taxonomies and thesauri, provide a consistent set of terms to describe the what of information in a structured way. 

[Slide 6] Concept Schemes. The Purpose of concept schemes is to define the types and structures of metadata used for describing a collection of resources. For example, Dublin Core is a well-known concept scheme that provides a standard set of metadata elements for describing digital resources. Concept schemes are prescriptive, outlining how information should be organized and presented to ensure interoperability.

[Slide 7] Semantic Schemes. The Purpose of semantic schemes is to provide a controlled set of terms and relationships for describing the content itself, ensuring consistency and clarity. For example, 

  • Taxonomies organize concepts into hierarchical “is a” or “part of” relationships, creating a structured tree for concepts.
  • Thesauri are a type of controlled vocabulary that includes preferred terms, synonyms (variant terms), broader terms, narrower terms, and related terms.
  • Authority Files are controlled vocabularies specifically used for authoritative lists of names of people, organizations, places, and other entities.
  • Ontologies are more complex semantic schemes that define concepts and their relationships with greater specificity than a thesaurus or taxonomy.

Semantic schemes aim to unify meaning and improve information retrieval by ensuring that terms are used consistently and unambiguously across a collection.

[Slide 8] A W3C Application Profile is a specification that defines a particular way of using one or more base specifications to achieve a specific function or interoperability goal within a community of practice. 

[Slide 9] Constraints on Base Specifications. An application profile doesn’t create entirely new web standards but rather specifies how existing W3C Recommendations (like RDF, SKOS, or DCAT specifications) should be used in a particular context. This might involve limiting the use of certain features, requiring specific data types or vocabularies, or defining how different specifications interact.

[Slide 10] Interoperability. The primary goal of an application profile is to facilitate out-of-the-box interoperability between different systems or applications within a defined domain. By adhering to a common profile, developers can ensure that their implementations can seamlessly exchange information and interact with each other.

[Slide 11] Community of Practice. Application profiles are often developed to address the specific needs of a particular community or industry sector. For example, a profile might be created for sharing learning resource metadata (LRMI), for creating Dublin Core applications (DCAP), for tabular Dublin Core application profiles (DC TAP), or for sharing knowledge organization systems (NKOS AP).

[Slide 12] Resources

Data Catalog Vocabulary (DCAT) – Version 3 (https://www.w3.org/TR/vocab-dcat-3/), an RDF vocabulary designed to facilitate interoperability between data catalogs published on the Web. W3C Recommendation (22 August 2024)

DCAT-AP 3.0 (https://semiceu.github.io/DCAT-AP/releases/3.0.0/), a DCAT profile for sharing information about catalogs containing datasets and data services descriptions in Europe. SEMIC Support Centre (14 June 2024) 

DCTAP (https://www.dublincore.org/specifications/dctap/) Dublin Core Application Profiles Working Group (n.d.)

Dublin Core Application Profile Guidelines (https://www.dublincore.org/specifications/dublin-core/application-profile-guidelines/)  (2005-09-03)

Gist: an open-source ontology (https://www.semanticarts.com/gist/), an upper-level ontology containing a minimal set of concepts required for most business applications, developed and maintained by Semantic Arts since 2012.

Guidance on Publishing Application Profiles of Vocabularies (https://www.w3.org/2017/dxwg/wiki/Guidance_on_publishing_application_profiles_of_vocabularies). W3C Dataset Exchange Working Group (last edited on 10 October 2025)

Networked Knowledge Organization Systems Dublin Core Application Profile (NKOS AP) (https://nkos.dublincore.org/nkos-ap.html) DCMI NKOS Task group (2019-11-03)

The Profiles Vocabulary (https://www.w3.org/TR/dx-prof/), an RDF vocabulary created to allow the machine-readable description of profiles of specifications for information resources. W3C Working Group Note (18 December 2019)

 

Heather Hedden Materials

Download Presentation | PDF

Related The Accidental Taxonomist Blog Posts

 

Lief Erickson Materials

 

Noz Urbano Materials

 

Peter Winstanley Materials

Download Presentation | PDF