Nov. 6, 2003 MAVIS MARCXML, MODS and Dublin Core MAVIS Users Conference 2003 Rebecca Guenther Library of Congress

Nov. 6, 2003MAVIS Users2 Overview of presentation Why MARC in XML MARCXML environment MODS Dublin Core Comparisons

Nov. 6, 2003MAVIS Users3 The MARC format Markup: data element set Semantics: meaning of elements (but content defined by other standards) Structure = syntax for communication 2709 MARCXML MARC 21: an international descriptive metadata format

Nov. 6, 2003MAVIS Users4 MARCXML evolution Need to take advantage of XML Establish standard MARC 21 in an XML structure Need simpler (but compatible) alternatives Development of MODS Need interoperability with different schemas Assemble coordinated set of tools Need continuity with current data Provide flexible transition options

Nov. 6, 2003MAVIS Users5 MARC in XML Why make transition to XML? To take advantage of emerging tools and systems that function through XML To make MARC compatible with new initiatives in the XML environment such as ZING (Z39.50 International Next Generation) OAI (Open Archives Initiative harvesting) METS (Metadata Encoding & Transmission Schema) DC (use data from Dublin Core in MARC environment) ONIX (use data from ONIX in the MARC environment)

MARC 21 evolution to XML

MARC 21 (2709) record (machine view) 00967cam a s1994 wauab eng a a (acid-free, recycled paper) :c$14.95 aDLCcDLCcDLC 00aGV1046.G3bG a796.6/4/ aSlavinski, Nadine,d aGermany by bike :b20 tours geared for discovery /cNadine Slavinski. aSeattle, Wash. :bMountaineers,cc1994. a238 p. :bill., maps ;c22 cm. 0aBy bike aIncludes index. 0aBicycle touringzGermanyxGuidebooks.

Nov. 6, 2003MAVIS Users8 MARC 21 in XML – MARCXML MARCXML record XML exact equivalent of MARC (2709) record Lossless/roundtrip conversion to/from MARC 21 record Simple flexible XML schema, no need to change when MARC 21 changes Presentations using XML stylesheets LC provides converters (open source) Standardization allows for communication and standard transformations

MARC21 (2709) to MARCXML 00967cam a s1994 wauab eng (acid-free, recycled paper) : $14.95 DLC GV1046.G3 G /4/ Slavinski, Nadine, 1968-

MARCXML record (continued) Germany by bike : 20 tours geared for discovery / Nadine Slavinski. Seattle, Wash. : Mountaineers, c p. : ill., maps ; 22 cm. By bike Includes index. Bicycle touring Germany Guidebooks.

Nov. 6, 2003MAVIS Users11 MARCXML – other tools Tagging transformations with XSLT stylesheets Name instead of number tags? Different language tags for MODS? Allows flexibility for display Character set transformations MARCXML to FRBR tool (for experimentation) MARC record validation tool

Nov. 6, 2003MAVIS Users12 What is MODS? Metadata Object Description Schema Bibliographic element set Initiative of Network Development and MARC Standards Office at LC Uses XML Schema Specifically for library applications, although could be used more widely A derivative (and subset) of MARC elements

Nov. 6, 2003MAVIS Users13 Why MODS? XML (Extensible Markup Language) is the markup for the Web Investigating XML as a new more flexible syntax for MARC element set Need for rich descriptive metadata in XML but simpler than full MARC, especially for complex digital library objects

Nov. 6, 2003MAVIS Users14 Potential Uses of MODS Need for a rich (but not too rich) XML metadata format for emerging initiatives as a Z39.50 Next Generation specified format as an extension schema to METS (Metadata Encoding and Transmission Standard) to represent metadata for harvesting (OAI) As an interoperable core for convergence between MARC and non-MARC XML descriptions For original resource description in XML syntax For packaging metadata with a resource

Nov. 6, 2003MAVIS Users15 Advantages of MODS Element set is richer than Dublin Core Hierarchy allows for rich description of complex digital objects Element set is more compatible with library data than ONIX or DC Element set is simpler than the full MARC format (MARCXML is entire format in XML syntax)

Nov. 6, 2003MAVIS Users16 Features of MODS Uses language-based tags Elements generally inherit semantics of MARC Some data has been repackaged; in some cases what is in several data elements in MARC may be brought together into one in MODS MODS does not assume the use of any specific cataloging code Reuse element descriptions throughout the schema Not intended to be a MARC replacement

Nov. 6, 2003MAVIS Users17 Limitations of MODS Because it’s a subset of MARC fields, a conversion retains core data and loses other data Does not allow for a round-trip mapping to and from MARC Content rules are not covered by MODS, although definitions of elements come from MARC

MARCXML to MODS Germany by bike : 20 tours geared for discovery / Slavinski, Nadine, creator text wau Seattle, Wash. : Mountaineers, c monographic eng 238 p. : ill., maps ; 22 cm. Nadine Slavinski. Includes index.

MODS (continued) Bicycle touring Germany Guidebooks. GV1046.G3 G /4/0943 By bike (acid-free, recycled paper) : DLC

Nov. 6, 2003MAVIS Users20 MODS at LC Minerva project metadata Web archiving project OAI metadata server for some American Memory collections Allow for richer metadata; choice of DC, MODS or MARCXML Incorporation with XML resources AV Prototype project; IHAS Developing tools for METS and MODS

Nov. 6, 2003MAVIS Users21 MODS Minerva record FranUlmer.com -- Home Page Fran Ulmer, Democratic candidate for Governor, Alaska, 2002 Ulmer, Fran Web site eng text/html image/jpg

Nov. 6, 2003MAVIS Users22 MODS Minerva record (continued) Web site promoting the candidacy of Fran Ulmer, Democratic... Elections Alaska Governors Alaska Election Democratic Party (AK) Election 2002 Web Archive cgi1.alexa.com/e2002/*/

Nov. 6, 2003MAVIS Users23

Nov. 6, 2003MAVIS Users24 Other MODS projects MusicAustralia MODS as exchange format between National Library of Australia and ScreenSoundAustralia Switched from DC-Library application profile Descriptive metadata extension schema used with METS for many digital library projects University of California Press Merges metadata from library catalog and non-MARC metadata from UC Press via MODS Schema used with bibliographic citations

Nov. 6, 2003MAVIS Users25 What is the Dublin Core Metadata Element Set? Overall governing body: DCMI Descriptive metadata 15 data elements with semantics (DCMES) Syntax is not mandated (but model and usage largely based on RDF) Not a system or format Does not define content rules

Nov. 6, 2003MAVIS Users26 What uses did the designers expect? Resource discovery and retrieval Facilitate searching on the Web Provide fielded searching Provide metadata simultaneously with data But may exist as separate record Allow inclusion of templates for record creation Serves as basis for a fuller record

Nov. 6, 2003MAVIS Users27 Dublin Core Metadata Initiative Dublin Core Metadata Element set DC Simple DC Qualified All elements are repeatable, optional, extensible Concept of an application profile Define content rules (repeatability, required elements) Combine elements from different metadata schemes Give best practice for an application

Nov. 6, 2003MAVIS Users28 The Dublin Core Metadata Element Set Title Author or Creator Subject and Keywords Description Publisher Contributor Date Resource Type Format Resource Identifier Source Language Relation Coverage Rights Management

Nov. 6, 2003MAVIS Users29 DC Interoperability Qualifiers Set of approved qualifiers, March 2000 Principles of qualification element refinements (refine meaning of element) e.g. alternative (qualifier of title) encoding schemes (aid in the interpretation of a value) e.g.LCSH Notion of “dumb down” Limited adoption Difficulty in layering complexity onto simplicity Qualifiers expressed as separate elements

Nov. 6, 2003MAVIS Users30 DCMI mission and scope Mission of DCMI: to make it easier to find resources using the Internet through the following activities: Developing metadata standards for discovery across domains Defining frameworks for the interoperation of metadata sets Facilitating the development of community or disciplinary specific metadata sets that are consistent with items 1 and 2

Nov. 6, 2003MAVIS Users31 DC Implementations Interdisciplinary and international recognition as the lingua franca for resource discovery metadata for electronic resources Variety of sectors and subject areas (archives, museums, science, mathematics, libraries, medicine, etc.) Government endorsed metadata OAI Prism Adobe

Nov. 6, 2003MAVIS Users32 Dublin Core successes International acceptance as the lingua franca of metadata Broad adoption across diverse applications Hundreds of DC based projects Attempts to broaden the initiative to be a focal point for metadata discussions Provides a resource description standard for communities that don’t have one

Nov. 6, 2003MAVIS Users33 Dublin Core failures Difficulty in defining a clear scope Tension between simplicity and complexity Lack of content rules, required elements Lack of search engine support Flat structure cannot be used for complex objects Lack of schema standardization May imply RDF implementation to fully use All implementations require adaptations, limiting interoperability

Nov. 6, 2003MAVIS Users34 Differences between MODS and Dublin Core MODS has structure Names Related item Subject MODS fits better in library environment Semantics Conversions Relationships between elements MODS includes record management information

Nov. 6, 2003MAVIS Users35 Using DC or MODS DC simple as a “lowest common denominator” between diverse metadata schemes DC for interoperability at coarse level Qualified DC still needs work Most DC implementations use local adjustments (resulting in less interoperability) XML schema for qualified DC not fully complete MODS useful for compatibility with existing bibliographic data embedded descriptions in relatedItem

Nov. 6, 2003MAVIS Users36 Metadata Crosswalks Dublin Core-MARC ONIX-MARC FGDC-MARC MODS-MARC UNIMARC-MARC GILS-MARC

Nov. 6, 2003MAVIS Users37 For further information