Open Annotation Core Data Model (tutorial)

West Coast Open Annotation Rollout April 9th 2013, Stanford, CA, USA 1 Open Annotation Community Group

http://www.w3.org/community/openannotation/

Open Annotation Data Model: Core

Robert Sanderson [email protected] Los Alamos National Laboratory @azaroth42 Paolo Ciccarese [email protected] Harvard Medical School @paolociccarese (Community Group Co-Chairs)



What is Annotation?

An Annotation is considered to be a set of connected resources, typically including a body and target, where the body is related to the target.

“ ”

Highlighting, Bookmarking Commenting, Describing Tagging, Linking Classifying, Identifying Questioning, Replying Editing, Moderating

Users Annotate To:

…Provide an Aide-Memoire …Share and Inform …Improve Discovery …Organize Resources …Interact with Others …Create as well as Consume



Open Annotation Data Model

Follow along: http://www.openannotation.org/spec/core/



Core Data Model

Annotation: The conceptual linkage between body and target Body: The comment or resource which is “about” the Target Target: The resource which is being discussed



Core Data Model

Annotation: Represents the relationship between Body and Target



Core Data Model



Core Data Model

<x:MyAnno> a oa:Annotation ; oa:hasBody <http://www.youtube.com/watch?v=fgg2tpUVbXQ> ; oa:hasTarget <http://zebu.uoregon.edu/hudf/hudf_300dpi.jpg> .



Core Data Model: Types

Useful to know the general type of the Body and Target. Useful to know the media type of the representation. Recommendation to use Dublin Core Types vocabulary.







<x:MyAnno> a oa:Annotation ; oa:hasBody <http://www.youtube.com/…> ; oa:hasTarget <http://zebu.uoregon.edu/…> .

<http://www.youtube.com/…> a dctypes:MovingImage ; dc:format “application/flv” .

<http://zebu.uoregon.edu/…> a dctypes:Image ; dc:format “image/jpeg” .



Core Data Model: Embedded Bodies

Many (existing and previous) systems embed textual bodies within the annotation document, as a literal string.

However Bodies are not just textual! However string literals are easy and currently common!

However literals aren’t part of the web architecture, and have no identity. You can’t associate arbitrary additional information with them!

However you don’t really need to. Resources will mean no one implements the data model!

However …




Embed a text comment! With a string literal!

Reference a video file! With a URI!




Solution: W3C’s Content in RDF specification






Core Data Model: Tagging

Tagging is the simplest form of Annotation Two forms:

•  Plain Text Tags •  Tagging with a string, typically a single word

•  Semantic Tags •  Tagging with URI that identifies a concept •  Tagging with a document, standing for a concept




Plain Text tagging uses Content in RDF, and adds the oa:Tag class







Semantic tagging uses the basic model, and adds the oa:SemanticTag class







Common to use a document as a “semantic” tag This is not good practice, and the data model adds an intermediate node






Core Data Model: Fragment URIs

Most non-tag Annotations are about segments of a resource Web Architecture uses URI Fragments to identify and describe segments Examples: •  http://www.example.com/index.html#para1 •  http://www.example.com/image.jpg#xywh=10,10,200,300

Good for simple segments, but not sufficient for all cases.




Fragment URIs use the basic model









Core Data Model: No Body

Annotations may only have an implicit body Examples:

•  Bookmarking •  Highlighting



Core Data Model: No Body



Core Data Model: Multiple Bodies & Targets

Annotations may have multiple bodies and targets Each body applies individually to each target



Core Data Model: Multiple Bodies & Targets



Core Data Model: Provenance

It is important to record the provenance of the Annotation •  Who was the person who created the annotation?

•  Needed for spam, reputation models, etc. •  When did they do it?

•  Needed for synchronization •  Who serialized the annotation to the document format?

•  Useful for debugging, advertising •  When did they serialize it?

•  Deduplication, debugging, synchronization









Core Data Model: Provenance Agents

Classes of Agent:

•  Person •  Organization •  Software

Properties of Agents: •  Name •  Email address •  Home page •  OpenID •  (other FOAF properties)

Useful to know additional information about the agents involved.









Core Data Model: Motivations

We know the what, who and when… need to know the why •  Introduce a Motivation class, separate from Annotation class. •  Uses the SKOS Concept ontology to provide richness and cross-

community resolution. •  Spec gives advice on how to create your own Motivations when

necessary.




Motivation Description oa:bookmarking Recording a resource or point of interest oa:classifying Assigning a class to a resource oa:commenting Providing a review or comment oa:describing Describing the resource oa:editing Requesting a change to the resource oa:highlighting Region or span of interest to highlight oa:identifying Assigning an identifier to a resource oa:linking Linking another resource to the target oa:moderating Assignment of value or quality oa:questioning Asking a question about the resource oa:replying Replying to previous statement or q. oa:tagging Tagging a resource










Thank You

Robert Sanderson [email protected] Los Alamos National Laboratory @azaroth42 Paolo Ciccarese [email protected] Harvard Medical School @paolociccarese (Community Group Co-Chairs)

http://www.w3.org/community/openannotation/ http://www.openannotation.org/

http://www.flickr.com/photos/hinkeb/5232293964/

Technology

Open Annotation Core Data Model (tutorial)