What’s new at schema.org?
According to Dan Brickley (here), changes start with two issues at the vocabulary level. The first is the addition of http://schema.org/sameAs, for disambiguating entities in structured markup, indicating when a single real-world entity is being described. The W3C proposal for the property, which essentially has the same semantics as owl:sameAs and which began life as sameThingAs, adds a property to Thing that makes it easier to indicate identifying URLs for entities being described. Reports Freebase, “This lets webmasters declare how their structured data should connect to the Knowledge Graph and opens up a lot of possibilities for mashups with the Freebase APIs.” Also in the mix, the Schema Bib Extend Group’s submission for http://schema.org/citation was promoted to CreativeWork, from MedicalScholarlyArticle. As pointed out by the proposal, since a citation or reference to another creative work can be found within any kind of document – not just medical/scholarly articles – the property should be available on the CreativeWork Type. If you’re interested in seeing what other proposals are being made for schema.org, and their status, take a look here. Another long-standing issue, Brickly remarks, has been closed – that is, that schema.org properties did not de-reference, as schema.org persons do. Now, he says, every property does. “This,” he writes, “is currently quite basic but should be useful in a number of ways. It helps with property-centric schemas such as LRMI (e.g.http://schema.org/learningResourceType ) and provides a foundation for publishing other useful pieces of information about each property(source/attribution, mappings, inverses and super-properties etc.).” This spring, in a schema.org revision, additions were made around LRMI, the Learning Resource Metadata Initiative, which The Semantic Web Blog covered here. Schema.org also now has per-property pages, and the Type, Enumeration and the new Property pages each have basic embedded RDFa/RDFS schema descriptions, he notes. Pages for Enumerations now use '::' instead of '>' to indicate type membership, as well. Here's an example he provides: "Previously, the presentation of Hardcover was like this:
Thing > Intangible > Enumeration > BookFormatType > Hardcover
We now show this: Thing > Intangible > Enumeration > BookFormatType :: Hardcover
... to make it slightly clearer that Hardcover is modeled as an instance."