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Difference between revisions of "Context Data Model"

(Introduction)
(The HOWL Ontology)
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[[HGG]] also differs from RDF on a purely syntactic (semantically lossless) level. In RDF an object may have N properties of type T each of which has a single value whereas in [[HGG]] an object may only have 0..1 properties of type T but if it exists it may only have have 1..N values. Further, in [[HGG]] these properties are called [[Attribute]]s.
 
[[HGG]] also differs from RDF on a purely syntactic (semantically lossless) level. In RDF an object may have N properties of type T each of which has a single value whereas in [[HGG]] an object may only have 0..1 properties of type T but if it exists it may only have have 1..N values. Further, in [[HGG]] these properties are called [[Attribute]]s.
  
== The HOWL Ontology ==
 
The [[HGG]] provides a description of its own model in OWL. This description is called [[HOWL]] (higgins.owl). Due to the differences in underlying identifiers, this description is only an approximation, albeit a very useful one. It enables Higgins developers to use RDF and OWL tools and technologies in the development of Higgins applications and [[Context Provider]]s without any modifications.
 
  
[[HOWL]] is an abstract (sometimes called an "upper") ontology for identity information. It is abstract in that it doesn't describe any concrete attributes such as "email address" or "first name". It also doesn't define very specialized classes of objects such as "calendar event" or "student", "movie", "book", etc. These are left to [[Context Provider]]s to define for themselves.
 
  
 
== Domain Concepts ==
 
== Domain Concepts ==

Revision as of 04:46, 3 March 2008

Introduction

Although it can be used for almost any kind of data, the focus of the Higgins Global Graph (HGG) is to provide a foundation for integrating, unifying, and sharing identity-related data. In particular we are focused on information about a person, a group or an entire organization. This might include contact information, authentication data, preferences, email addresses, interests, employer-related information. An object representing a single person, might have relationships to other objects and other people in the same or different data contexts.

See

Core Semantics

The HGG is based on the core semantics of the W3C's Resource Description Framework (RDF). The subtle but important differences between HGG and RDF are derived from differences in the choice of identifiers used to identify objects in each model. RDF is based on pure HTTP URIs, whereas HGG is based on a more generalized URI called a Higgins Identifier. Objects identified by URIs in RDF are called Resources, whereas in HGG they are identified by Higgins Identifiers and are called Nodes.

HGG also differs from RDF on a purely syntactic (semantically lossless) level. In RDF an object may have N properties of type T each of which has a single value whereas in HGG an object may only have 0..1 properties of type T but if it exists it may only have have 1..N values. Further, in HGG these properties are called Attributes.


Domain Concepts

The Higgins Global Graph defines these Concepts (listed alphabetically):

  1. Attribute
  2. Context
  3. ContextId
  4. Context Relation
  5. Context Correlation
  6. Data Range --formerly Attribute Value Datatype
  7. Entity
  8. Node --formerly Digital Subject
  9. NodeId
  10. Node Relation
  11. Node Correlation

Higgins Ontology Language (HOWL)

Extending HOWL

HOWL is a base ontology. To be useful in real-world applications developers must develop specialized ontologies based on HOWL that describe a specific concrete domain.

For example, if a developer wanted to describe a CRM database, she would create an OWL ontology that would describe the data objects in the CRM database. This CRM database is called a Context in Higgins. If, for example, the database contained records about customers and those customers had full-names and email addresses, then the developer would define "Customer" as a sub-class of Node and "full-name" and "email" as kinds of Attributes.

Here are some HOWL-based Ontologies (note - these need to be updated):


Open Issues

References

RDF/OWL Related Resources

Misc Resources

Links

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