Lee Iverson - How does the web connect content?

Semantic Pragmatics Lee Iverson UK Museums and the Web

Connecting Museum Museum Users Users ??? ???

Why to connect?

Referral

Let users know about other museums

Enhancement

Improve information about your collection

Personalization

Improve relevance to each user

…

The Powerhouse

Becoming Connected

Expose own data

Find other data

Integrate

Engage with users

Exposing Data

Museums manage structured, authoritative data about collections

but

Museum web sites are dominated by presentation and control

Results:

Museum web data is hermetically sealed

User experience is completely controlled

Exposing Data

Give it away as structured data

Must decide private/public boundary

Creative commons licensing

Easy to do via web (hint: XML or RDF)

Benefits:

Aggregation possibilities

Museum to museum links possible

Consumers can repurpose data

New uses means new customers

How?

Add links to structure from:

Main page

Individual pages

Objects and exhibits

Visible links?

Meta links! (e.g. RSS)

Standardize

Which standards?

Which vocabularies?

Standards Strategy

Standard = agreement between min. 2 parties to do something in same way

Pragmatics:

Use existing standards as much as possible

Never standardize more than minimum

That which is necessary for essential functionality

Never standardize vaporware

Recognize defacto standards rather than create new ones

Is this the Semantic Web?

Maybe

Meaning vs. Presentation

Machine vs. Human

Maybe not

Where is the meaning ?

Where is the reasoning ?

Berners-Lee

“ I have a dream for the Web [in which computers] become capable of analyzing all the data on the Web – the content, links, and transactions between people and computers. A ‘Semantic Web’, which should make this possible, has yet to emerge, but when it does, the day-to-day mechanisms of trade, bureaucracy and our daily lives will be handled by machines talking to machines. The ‘intelligent agents’ people have touted for ages will finally materialize.”

– Tim Berners-Lee, 1999

Syntax vs. Semantics

In a certain sense structure and vocabulary is the semantics

Semantics:

Ability to interpret

Repurposability

Mirroring human interpretation

Finding Data

Linking to other museums and sites…

Spider and scrape

Tools: Calais?

Unreliable, expensive, needs moderation

Rely on structured data

RSS or Atom

You show me yours…?

Integration

Relate your content to theirs

Relate structure

Relate vocabulary

Relate context

It is possible!

Reciprocal Research Network

Straight from CMS

http://rrnpilot.org

Data for Integration

XML

Information model

One syntax

Schema from structure

Integration by structural integration

RDF

Data model

A few syntaxes

Schema from vocabulary

Integration by reference

RDFa

RDF in XHTML:

Best of both worlds

Microformat-like attributes on XHTML content

Need to match XML structure to RDF classes

Ordinary web pages can be “data web” pages

RDF

Resource description framework

Metadata language

Simple, unambiguous data model

Model built on reference , so statements can be detached from their referents

Foundation for:

RSS – RDF Site Summary

DAML+OIL and OWL ( Semantic Web )

RDF Model

RDF document is set of statements

Statement is triple :

Subject – a URI reference

Property – a URI reference

Object – a value (may be URI)

RDFS (RDF Schema)

Restrict subject/object values based on property

Property URI contains description of constraints

RDF Example

@prefix dc: <http://purl.org/dc/elements/1.1/> .

@prefix foaf: <http://xmlns.com/foaf/0.1/> .

<http://example.org/> dc:creator _:b .

_:b foaf:name "Bob" .

“ A person named Bob is the creator of http://example.org”

http://example.org _:b dc:creator “ Bob” foaf:name

RDF Schema Example

<rdf:Property rdf:about="http://xmlns.com/foaf/0.1/name"

rdfs:label="name"

rdfs:comment="A name for some thing.">

<rdfs:range

rdf:resource="http://www.w3.org/2000/01/rdf-schema#Literal">

</rdfs:range>

<rdfs:isDefinedBy

rdf:resource="http://xmlns.com/foaf/0.1/">

</rdfs:isDefinedBy>

<rdfs:subPropertyOf

rdf:resource=

"http://www.w3.org/2000/01/rdf-schema#label">

</rdfs:subPropertyOf>

</rdf:Property>

What About Semantics?

DAML+OIL or OWL provide:

Vocabulary of basic properties

Mappings from these properties to formal semantics

Language for defining new, semantically well-defined properties

Language for expressing logical inferences that can be made within vocabulary

What is an Ontology?

Formal (but uninformative):

“ A specification of a conceptualization”

Informal

“ A shared vocabulary designed to support the communication of the meaning of a certain class of resources”

“ An attempt to make semantics of a body of knowledge more explicit”

Technical:

“ A vocabulary and logical inference statements expressed in a formal language (e.g. OWL) for describing a set of resources”

A Simple Ontology Cat Dog Cheetah Species category-type category-type category-type Feline Canine Mammal kind-of kind-of kind-of kind-of kind-of disjoint disjoint disjoint hates

McBride’s 4 Steps for Widespread Adoption