Jennifer Bowen, University of RochesterDC-2010 Conference October 20, 2010, Pittsburgh, PA

Moving Library Metadatatoward Linked Data: Opportunities Provided by the eXtensible Catalog

About me…

Currently:- Librarian- Technical services administrator- Software development team co-leader

Formerly:- Cataloger (MARC)- Standards developer (RDA)

Maybe someday…Linked Data Expert?

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My Topics Today

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Is it feasible to turn legacy library MARC metadata into Linked Data in an automated environment,

and,How can eXtensible Catalog (XC) software play a role in that process?

Image source: www.blog.kdl.org

Semantic Web and Linked Data

Semantic Web: a set of technologies that allow computers to understand the meaning of information on the web

Linked Data: a mechanism for exposing, sharing and connecting data on the web, using identifiers and relationships

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Linked Data “Expectations of Behavior”

– Use URIs as names for things – Use HTTP URIs so that people can look up

those names. – When someone looks up a URI, provide useful

information, using the standards (RDF*, SPARQL)

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

Tim Berners-Lee, “Design issues”, 2006 http://www.w3.org/DesignIssues/LinkedData.html

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Linked Data: RDF triple

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This presentation Jennifer Bowen

has creator

ObjectPredicateSubject

“Linking Open Data cloud diagram, by Richard Cyganiak and Anja Jentzsch. http://lod-cloud.net/”

A Reality Check

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Teaching MARC metadata new tricks?

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Image source: http://www.englishcafe.com/node/2337

Turning legacy data into Linked Data…

How do we even get started?

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Getting Started

To create Linked Data, we need:–Software to transform legacy data–Analysis: mapping of legacy metadata to

Linked Data properties

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The software…

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eXtensible Catalog (XC) is open source, user-centered, next generation software for libraries.

XC provides a discovery system and a set of tools for libraries to manage metadata and build applications.

XC Software Components

User Interface Website on Drupal CMS

Integrated Library System Repository

XC User Interface

Metadata Processing Metadata Services Toolkit

Connectivity tools NCIPToolkit

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OAI Toolkit

XC’s original metadata goals

- Aggregate MARC and other metadata for use in new applications

- Define a FRBR-based metadata schema to support XC’s user-interface functionality

- Create a software application to process batches of metadata through a set of services

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Software development:a moving target!

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XC and Linked Data

How can XC help move legacy library metadata closer to Linked Data?

NOT among XC’s original goals

However, XC software creates an opportunity to contribute to this effort and provides important “lessons learned”

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Converting MARC to Linked Data

What XC software can do:– Convert MARC codes to vocabulary values– Remove extraneous data– Normalize inconsistencies– Map most MARC fields/subfields and parse to

appropriate FRBR Group 1 entity records

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Converting MARC to Linked Data

Problematic areas:– Some MARC fields/subfields are difficult to

map to appropriate FRBR entities – Tracking relationships between FRBR entity

records: How many relationships can we support with XC software?

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MARC to XC Schema Transformation

Parses MARCXML records into linked FRBR-based records Maps MARCXML data

elements to Linked-Data-Compatible elements in the XC Schema.

Managing Relationships

Managing Relationships

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Issue: Managing Multiple Relationships

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MARC bibliographic records can refer to multiple FRBR entities of the same type (analytics that represent multiple works/expressions, e.g. tracks on a CD)

Issue: Beyond FRBR Group 1 Entities

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MARC “Alternate Graphic Representation” (880 fields) can contain data that belong in records for Group 2 and Group 3 entities

Contributor:700 1    ‡6 880‐08 ‡a Vasil’ev, Maksim.880 1    ‡6 700‐08 ‡a Васильев, Максим.

Subject:600 10 ‡6 880‐06 ‡a Putin, Vladimir Vladimirovich, ‡d 1952‐880 10 ‡6 600‐06 ‡a Путин, Владимир Владимирович, ‡d 1952‐

If we were to parse this 880 data correctly:

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Alternative script of

name from 880

Alternative script of subject

from 880

Issue: Related Group 1 Entities

Language attribute for a related expression

041  1    ‡a eng ‡h ita100  0    ‡a Dante Alighieri, ‡d 1265‐1321.240  10 ‡a Divina commedia. ‡l English245  14 ‡a The divine comedy / ‡c Dante ; a     new verse translation by C.H. Sisson.

500        ‡a Translation of: Divina commedia.

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If we were to parse 041 ‡h data…

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Alternative script of

name from 880

Original language from

041 ‡h

Alternative script of subject

from 880

Managing Relationships Between Entities

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Original language from

041 $h

Alternative script of subject

from 880

Alternative script of

name from 880

•new records•changed records•deleted records•changed relationships

Maintaining links between separate FRBR entity records in a production environment monopolizes system resources and may not be scalable.

What we are learning from XC

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But wait…

If we can map a MARC data element to a FRBR entity, we can probably convert it to Linked Data.

What does this emphasis on FRBR have to do with Linked Data?

FRBR Group 1 Entities

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But do we have to?

- Do we have to be able to map MARC elements to a FRBR entity in order to create Linked Data?

- Would managing RDF triples be more scalable than managing FRBR-based records and the relationships between those records?

Best Practices for Linked Data

- Unique identifiers for XC metadata records

- Data elements from registered schemas- Registered vocabularies

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By attempting to follow best practices in XC for Linked Data, we hope to facilitate eventual output of XC metadata in RDF.

RDF Triple

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This resource Poets, American

has subject

ObjectPredicateSubject

URIs for each?

RDF Triple – Record identifiers

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ObjectPredicateSubject

oai:mst.rochester.edu: MST/MARCToXCTransformation/10081

This resource has subject Poets, American

Identifiers for XC Schema records

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<?xml version="1.0" encoding="UTF-8"?><xc:frbr xmlns:xc="http://www.extensiblecatalog.info/Elements" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:rdvocab="http://rdvocab.info/Elements" xmlns:dcterms="http://purl.org/dc/terms/" xmlns:rdarole="http://rdvocab.info/roles"><xc:entity type="work" id="oai:mst.rochester.edu:MST/MARCToXCTransformation/10081"><dcterms:subject xsi:type="dcterms:LCC">PS3505.U334</dcterms:subject><dcterms:subject xsi:type="dcterms:DDC">811/.52</dcterms:subject><dcterms:subject xsi:type="dcterms:DDC">B</dcterms:subject><rdarole:author>Sawyer-Lauc<U+0327>anno, Christopher, 1951-</rdarole:author><rdvocab:titleOfTheWork>E.E. Cummings :</rdvocab:titleOfTheWork><xc:subject xsi:type="dcterms:LCSH">Cummings, E. E. (Edward Estlin), 1894-1962.</xc:subject><xc:subject xsi:type="dcterms:LCSH">Poets, American-20th century-Biography.</xc:subject></xc:entity></xc:frbr> A persistent, globally unique identifier

for each XC Schema record

RDF Triple - Registered Data Elements

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http://www.extensiblecatalog.info

/Elements/subject

ObjectPredicateSubject

oai:mst.rochester.edu: MST/MARCToXCTransformation/10081

This resource has subject Poets, American

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DCMI

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RDA

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XC

XC Schema “work” record: data elements

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<?xml version="1.0" encoding="UTF-8"?><xc:frbr xmlns:xc="http://www.extensiblecatalog.info/Elements" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:rdvocab="http://rdvocab.info/Elements" xmlns:dcterms="http://purl.org/dc/terms/" xmlns:rdarole="http://rdvocab.info/roles"><xc:entity type="work" id="oai:mst.rochester.edu:MST/MARCToXCTransformation/10081"><dcterms:subject xsi:type="dcterms:LCC">PS3505.U334</dcterms:subject><dcterms:subject xsi:type="dcterms:DDC">811/.52</dcterms:subject><dcterms:subject xsi:type="dcterms:DDC">B</dcterms:subject><rdarole:author>Sawyer-Lauc<U+0327>anno, Christopher, 1951-</rdarole:author><rdvocab:titleOfTheWork>E.E. Cummings :</rdvocab:titleOfTheWork><xc:subject xsi:type="dcterms:LCSH">Cummings, E. E. (Edward Estlin), 1894-1962.</xc:subject><xc:subject xsi:type="dcterms:LCSH">Poets, American-20th century-Biography.</xc:subject></xc:entity></xc:frbr> Data elements from registered

namespaces for DC terms, RDA roles and vocab, and XC

RDF Triple - Registered Vocabularies

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http://id.loc.gov/authorities/sh85103735#concept

http://www.extensiblecatalog.info

/Elements/subject

ObjectPredicateSubject

oai:mst.rochester.edu: MST/MARCToXCTransformation/10081

This resource has subject Poets, American

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<?xml version="1.0" encoding="UTF-8"?><xc:frbr xmlns:xc="http://www.extensiblecatalog.info/Elements" … xmlns:subjid=“id.loc.gov/authorities”><xc:entity type="work" id="oai:mst.rochester.edu:MST/MARCToXCTransformation/10081">…<xc:subject xsi:type="dcterms:LCSH">Poets, American-20th century-Biography.</xc:subject><xc:subject xsi:type="dcterms:LCSH” subjid=“sh85103735#concept”>Poets, American</xc:subject><xc:temporal>20th century</xc:temporal><xc:type>Biography</xc:type></xc:entity>

XC Work record with embedded URI for LCSH “Poets, American”

RDF Triple

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http://id.loc.gov/authorities/sh85103735#concept

http://www.extensiblecatalog.info

/Elements/subject

ObjectPredicateSubject

oai:mst.rochester.edu: MST/MARCToXCTransformation/10081

This resource has subject Poets, American

Experimenting with Linked Data

- Within a MARC or MARCXML environment? - Possible to give each record a

URI- MARC elements themselves

don’t have URIs- How to embed multiple URIs for

registered vocabularies in MARC?

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- XC enables experimentation outside of a MARC environment with data that originated as MARC

Making Linked Data a Priority for XC

– Balancing goals– Time/funding constraints– What’s our use case?– Output of Linked Data from XC vs.– Using Linked Data within XC?

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XC Linked Data Accomplishments

XC has set the stage for Linked Data by:- Providing a platform for creating Linked Data

using XC software - Ensuring that XC Schema records can be

converted to RDF triples as easily as possible- Enabling others to build upon what we have

accomplished done so far.

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Next Steps

- Monitor RDA implementations- Develop XC authority control service- Enable RDF output of XC Schema metadata- Encourage libraries to use XC software and

contribute to the XC user community - Seek funding for additional software

development

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www.eXtensiblecatalog.org

Jennifer Bowenjbowen@library.rochester.edu

Thank you! Questions?