Presentation about usability of linked data, following LODLAM 2020 at the Getty. Discusses JSON-LD 1.1, IIIF, Linked Art, in the context of the design principles for building usable APIs on top of semantically accurate models, and domain specific vocabularies.
In particular a focus on the different abstraction layers between conceptual model, ontology, vocabulary, and application profile and the various uses of the data.
11. @azaroth42
rsanderson
@getty.edu
IIIF:Interoperabilituy
TheImportanceof
BeingLOUD
@azaroth42
Successful APIs …
• Solve actual challenges, documented as use cases
• Using data that is captured and available
• Allow consistent implementation of shared use cases
• Allow for addition of further functionality
• Can be productively used
• Via easy-to-implement services
• With easy-to-implement applications
• Provide interoperability between data and systems
• Are clearly documented with relevant examples
20. @azaroth42
rsanderson
@getty.edu
IIIF:Interoperabilituy
TheImportanceof
BeingLOUD
@azaroth42
IIIF Design Patterns
1. Scope design through shared use cases
2. Design for international use
3. As simple as possible, but no simpler
4. Make easy things easy, complex things possible
5. Avoid dependency on specific technologies
6. Use REST / Don’t break the web
7. Separate concerns, keep APIs loosely coupled
8. Design for JSON-LD, using LOD principles
9. Follow existing standards, best practices, when possible
10. Define success, not failure (for extensibility)
https://iiif.io/api/annex/notes/design_patterns/
21. @azaroth42
rsanderson
@getty.edu
IIIF:Interoperabilituy
TheImportanceof
BeingLOUD
@azaroth42
Is IIIF Actually LOUD?
• IIIF is JSON-LD ... used as if it were JSON
• IIIF APIs are focused on Presentation, not Semantics
• Usability considered more important than Precision
• Document structure / graph boundary is enforced by
the API specifications
• Presentation: Collection, Manifest
• Image: Info.json
• Discovery, Search: Stream/Results, Page
22. @azaroth42
rsanderson
@getty.edu
IIIF:Interoperabilituy
TheImportanceof
BeingLOUD
@azaroth42
Is IIIF Actually LOUD?
• Discovery (and paging) use W3C ActivityStreams
• Also not very Linked
• Also very successful
• Annotations are the only core affordance that cross
institutional boundaries
• Services and Extensibility are important facets that
rely on Linked Data
• Image and Presentation 3.0 use JSON-LD 1.1 as it
is intended to be used …
29. @azaroth42
rsanderson
@getty.edu
IIIF:Interoperabilituy
TheImportanceof
BeingLOUD
@azaroth42
Linked Art Model
A Linked Open Usable Data model, collaboratively designed
to work across cultural heritage organizations, that is easy
to publish and enables a variety of consuming applications.
Design Principles:
• Focused on Usability, not 100% precision / completeness
• Consistently solves actual challenges from real data
• Development is iterative, as new use cases are found
• Solve 90% of use cases, with 10% of the effort
30. @azaroth42
rsanderson
@getty.edu
IIIF:Interoperabilituy
TheImportanceof
BeingLOUD
@azaroth42
Linked Art Collaboration
Working to formalize the profile, funded by Kress & AHRC
• Getty
• Rijksmuseum
• Louvre
• Metropolitan Museum of Art
• Smithsonian
• MoMA
• V&A
• NGA
• Philadelphia Art Museum
• Indianapolis Art Museum
• The Frick Collection
• Harvard University
• Princeton University
• Yale Centre for British Art
• Oxford University
• Academica Sinica
• ETH Zurich
• FORTH
• Zeri Foundation (U. Bologna)
• Canadian Heritage Info. Network
• American Numismatics Society
• Europeana
I think Many Sporny perfectly captured the sentiment: When developers hear “RDF” or “the Semantic Web” or “SPARQL” they think: Not in my back yard, people have died from that stuff!
Michael Barth has six fundamental features for API evaluation, which relate directly to the value of the API as a standard for use. This seems like a good starting point for standards for digital interoperability.
Abstraction Level -- is the abstraction of the data and functionality appropriate to the audience and use cases. An end user of the "car" API presses a button or turns a key. A "car" developer needs access to engine directly.
Comprehensibility -- is the audience able to understand how to use it to accomplish their goals
Consistency -- if you know the "rules" of the API, how well does it stick to them? Or how many exceptions are there to a core set of design principles
Documentation -- How easy is it to find out the functionality of the API?
Domain Correspondence -- If you understand the core domain of the data and API, how closely does the understanding of the domain align with an understanding of the data?
And what barriers to getting started are there?
There are two more that I think are important.
Need to have the rules of the game before two systems can interact
Need to have the rules of the game before two systems can interact
The core functionality. Not just an image tag, but also not photoshop on the web.
Just enough information to present the context of the images in a way that the user can understand what they’re interacting with. Structure of the object and its metadata in a pre-processed form for rendering in a client … so not a semantic metadata API.
The community engagement with JSON-LD has been unprecedented, notably due to Google’s adoption of it and the usability focus of schema.org.
Intent of a profile is to select only the relevant parts of the lower level definitions that are needed.
Further restrict the model / ontology to ensure that the data is usable.
Less important for IIIF to be complete as it’s about presentation not semantics. But for semantic description…
E22 HumanMadeObject is the ontology term for the class of Human Made Objects in the conceptual model, and type is the relationship between things and their classes.
The label is a constructed piece of text to label the resource, in the absence of any other data. Intended for developers looking at the data, not intended for directly being displayed to “real” humans.
Turns out that there are two sorts of things that speak in numbers … computers, and librarians.
That should help. We use the Getty’s Art and Architecture Thesaurus.
That should help. We use the Getty’s Art and Architecture Thesaurus.
We know that this is the primary name, because it was called title, not alternate title.
We know that this is the primary name, because it was called title, not alternate title.
And now we’re at the 50’ foot view, with an activity in the middle and who, what, when and where around the outside.
Models for all of these other entities as well to capture useful knowledge for shared use cases.
No one has all of the knowledge, and to try to gather everything together and keep it persistently available and up to date is impossible below the scale of Google.
No one has all of the knowledge, and to try to gather everything together and keep it persistently available and up to date is impossible below the scale of Google.