Linked Datafor Libraries, Archives, Museums

Learning objectives• Define the concept of linked data

• State 3 benefits of creating linked data and making it

available

• Outline the process of creating LD

• State how to make use of LD created by others

Basic Terms

Linked Data (LD)

"a term used to describe a recommended best practice for exposing, sharing, and connecting pieces of data, information, and knowledge on the Semantic Web using URIs and RDF."

http://linkeddata.org/faq

Linked Open Data (LOD)

Linked Data that is explicitly published under an open license.

Not all Linked Data will be open, and not all Open Data will be

linked

LOD-LAM

Linked Open Datain

Libraries Archives Museums

#lodlam

URI

Uniform Resource Identifier

A string of characters used to identify a name or resource on the Internet

RDF

Resource Description Framework

“a metadata data model. It has come to be used as a general method for conceptual description or modeling of information that is implemented in web resources, using a variety of syntax formats.”

Wikipedia

RDF

Defined statements compromising a subject, a predicate (property), and an object.

These statements are called “triples”

SPARQLSPARQL protocol and RDF Query Language

SPARQL Endpoint: “URL for a given set of RDF data that you can send queries to and get answers from”

Dorothea Salo

Linked Data (LD)Linked data “describes a method of publishing structured data so that it can be interlinked and become more useful. It builds upon standard Web technologies such as HTTP and URIs, but rather than using them to serve web pages for human readers, it extends them to share information in a way that can be read automatically by computers. This enables data from different sources to be connected and queried”

Wikipedia definition

Web of documentsvs.

Web of data

resource

resource

resource

resource

resource links to

links to

links to

links to

Diagram by Emily Nimsakont

links to

links to

links to

links to

links to

data links to

links to

links to

links to

data data

data

datadata

datadata

datadata

data

data

data

data

data

Diagram by Emily Nimsakont

Relationship grammar

Resource A Resource B

Describe resources using interrelated “statements” (RDF triples)

Use URIs – unique globally managed identifiers as the “words” of the statement

relatedTo

Slide by DCMI tutorial “What makes the Linked Data Approach Different”

Traditional metadata = Implicit Relationships

MARC Bibliographic Record

100 10 Smart, Laura J. ǂq (Laura Jean), ǂd 1971-

245 00 Women in Science ǂh [electronic resource].

Linked Data is Explicit

Laura J. Smart Women in ScienceisCreatorOf

Women in Science sdsc.edu/ScienceWomenisTitleOf

Object – predicate - subject

Triple with URIs

Laura J. Smarthttp://viaf.org/viaf/171972263

is creator ofhttp://purl.org/dc/terms/creator

Women in Sciencehttp://www.sdsc.edu/ScienceWomen

Under the hood

<?xml version="1.0" encoding="utf-8"?><rdf:RDF xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"xmlns:rdfs="http://www.w3.org/2000/01/rdf-schema#"xmlns:dc="http://purl.org/dc/elements/1.1/"<rdf:Description rdf:about="http://www.sdsc.edu/ScienceWomen"><dc:title>Women in Science</dc:title><dc:creator dc:source="http://viaf.org/viaf/171972263/" rdfs:Literal="Laura J. Smart" /></rdf:Description></rdf:RDF>

It’s the data, stupid.

“We’re not dealing with records anymore. We are working with interrelated nodes of data”

Diane Hillmann

What does it really look like?

“This is kind of like asking what electricity looks like: it doesn't so much look like anything, as it makes certain things possible”

Karen Coyle

Thinkbase

http://thinkbase.cs.auckland.ac.nz/start.jsp

Benefits of creating/using Linked Data

• Sharable• Extensible• Reusable• Multi-lingual• Reduce redundancy• Improve discoverability• Sophisticated navigation

Benefits of creating/using Linked Data

• Enhanced publications• Facilitate research • Separate semantics from syntax• Persistent URIs an aid to digital preservation• Drive users to your site• Collaborate with less licensing hassle (LOD)

All the kids are doing it

“The new bibliographic framework project will be focused on the Web environment, Linked Data principles and mechanisms, and the Resource Description Framework (RDF) as a basic data model.”

LC Bibliographic Framework for the Digital Agehttp://www.loc.gov/marc/transition/news/framework-103111.html

How to?

Other prerequisites: HTML. URIs.

“Learn about Resource Description Framework. Never look back.”

Rurik Greenall, Norwegian Institute Science & Technology

Berners-Lee Basic Linked Data Principles

1. Use URIs as names for things 2. Use HTTP URIs so that people can look up

those names3. When someone looks up a URI, provide

useful information, using the standards (RDF, SPARQL)

4. Include links to other URIs. so that they can discover more things.

Source: Heath & Bizer http://linkeddatabook.com/editions/1.0/

The process: 1st get your data

Feynman, Richard Phillips, 1918-1988 LCCN: n 50002729

http://viaf.org/viaf/44298691

http://lccn.loc.gov/n50002729

The process: Get your data into RDF/XML

Name LCCNRobert B. Phillips n 00014131 Keith C. Schwab nr2002032640

From here:

Robert Phillips http://lccn.loc.gov/n00014131

Creator http://purl.org/dc/terms/creator

Book title http://openlibrary.org/books/OL11358296MPhysical biology of the cell

To here:

The process: Expose that data

Learning objectives• Define the concept of linked data

• State 3 benefits of creating linked data and making it

available

• Outline the process of creating LD

• State how to make use of LD created by others

Thanks!library.caltech.edu/laura