The OpenURL Quality Problem & Project Adam Chandler Coordinator, Service Design Group Glen Wiley

1. The OpenURL Quality Problem & Project Adam Chandler Coordinator, Service Design Group Glen Wiley Metadata Librarian Metadata Working Group February 22, 2008

2. Reduce linking dead ends from a publisher’s content to another Show multiple subscriptions or relevant access points in one place Desire to show the most appropriate version of the service (like full text) Improve content visibility Possibly reduce document delivery costs The Original Problem

3. Originated by Herbert van de Stompel at Univ. of Ghent, around 2000 Became OpenURL Version 0.1 Commercialized by ExLibris (SFX) in 2001 Fast-tracked by NISO Released as Version 1.0, but officially as international ANSI standard Z39.88 in 2004 OCLC is maintenance agency as of June 2006 Brief History of OpenURL

4. What is OpenURL? • OpenURL is a syntaxfor querying a server • to perform a service • on a resource • specified by attributes • sensitive to context • also specified by attributes OpenURL is an "actionable" URL that transports resource metadata.

5. OpenURL Version 0.1 Example http://linkresolver.library.cornell.edu:4550/resserv?genre=article&issn=01604120&title=Environment+International&volume=32&issue=1&date=20060101&atitle=The+United+States+Department+of+Energy's+Regional+Carbon+Sequestration+Partnerships+program.&spage=128&pages=128-144&sid=EBSCO:aph&aulast=Litynski

6. OpenURL Version 1.0 Example http://linkresolver.library.cornell.edu:4550/resserv?url_ctx_fmt=info:ofi/fmt:kev:mtx:ctx&rfr_id=info:sid/www.isinet.com:wok:wos&rft.au=giordanino,+m&rft.epage=377&rft.stitle=knowl+eng+rev&rft.date=2007&rft_id=info:doi/10.1017%2fs0269888907001233/&url_ver=z39.88-2004&rft.issn=0269-8889&rft.aulast=uren&rft.title=knowledge+engineering+review&rft.genre=article&rft.issue=4&rft.spage=361&rft_val_fmt=info:ofi/fmt:kev:mtx:journal&rft.volume=22&rft.auinit=v&rft.atitle=the+usability+of+semantic+search+tools%3a+a+review

7. How does it work?

8. OpenURL Version 0.1 • OpenURL 0.1 is a de facto standard that is built around scholarly bibliographic data only • An accepted “standard” syntax for creating a link between an information source and a link resolver • Pre-defines sets of data elements to use in describing an “item” • Relies on HTTP protocol for transmission • The concept of context-sensitive linking implemented for a specific class of resources: (some) scholarly assets

9. OpenURL Version 0.1 Limitations: • Pre-defined metadata genres and elements means that new ones cannot be defined to meet emerging needs (e.g., for image databases) • Only provides for key-value pair (HTTP GET or POST) representation of metadata. • OpenURL 0.1 is tied to HTTP transport • Lack of implementation guidelines means that support for OpenURL is loosely defined

10. OpenURL Version 1.0 • Complicated and highly abstract • Designed for greater flexibility • Slower uptake • Supports richer data formats/genres • Journal, Article, Proceeding, Preprint, Book, Report, Document, Patent, Dissertation, etc • Provides more complete context description • Supports transport mechanisms other than HTTP • like SOAP, OAI-PMH, HTTPS • A generic specification that allows to implement OpenURL Applications • OpenURL Applications: networked applications that implement the concept of context-sensitive services for a certain class of resources

11. Resolver Transport Referent description of Referent & context reference about ContextObject services pertaining to Referent Understanding OpenURL Version 1.0 networked resource Diagram is from Herbert von de Sompel’s OpenURL Tutorial at the Olybris 2005 Ex Libris Seminar, Kos, Greece, April 18th 2005.

12. Understanding OpenURL Version 1.0 • OpenURL 1.0 divides ContextObject into six entities (including the resource) • Each entity has attributes to identify it • Each entity has schema for those attributes • Each entity affects URL resolution

13. Problems with the Standard & Documentation • Tough read • Key/Encoded-Value (KEV) “Implementation Guidelines” are helpful, but complex • Not specific enough in many ways. Some mention of best practices for metadata values like: • UTF-8 encoding for special characters • DCMI Type Vocabulary for Referent Type (rft.type) • MIME type for Referent Format (rft.format)

14. Miriam Blake citation and the Known Issues • M.E. Blake, F.L. Knudson. Metadata and Reference Linking. Libr. Coll. Acq. & Tech. Serv. 26 (2002) 219–230 229 • Goals for the future: • Increased consistency in metadata within a single database and across databases. • Increased communication between primary publishers and secondary publishers. • Increased awareness of bibliographic/citation standards by authors. • Increased outreach by librarians to authorsemphasizing and promoting the importance of citation standards for electronic document retrieval.

15. Link Resolvers and the Serials Supply Chain[UKSG Report] -- 2007 • Description of the Supply Chain • Issues and Barriers • Lack of awareness • Lack of Co-operation • Inaccurate/Incomplete Data • Content Package Issues • Responsibility of Data Quality • Lack of Data Standards • Inbound Linking Issues • Etc… • Recommendations

16. 1. Wrong start end date in the local library's holdings database 2. Wrong link-to syntax in link resolver 3. Inaccurate or missing Crossref DOI URL (often the DOI registration process is out of sync with the mounting of articles) Problems Persist

17. Problems Persist 4. Semantically inaccurate metadata from the OpenURL origin (wrong ISSN, for example)

18. Problems Persist 5. Syntactically incorrect metadata from the OpenURL origin

19. Problems Persist 6. Subscription and embargo errors (especially in January) • For each month that passes the chances of the link working is increased by over 8%

20. empirical network level problem: so it needs be solved at the network level sanctioned, officially recognized offer value to librarians and content providers narrow scope Characteristics of a solution to the OpenURL quality problem

21. Model: Open Language Archives Community Metadata Quality Evaluation: Experience from the Open Language Archives Community, Baden Hughes, Department of Computer Science and Software Engineering, University of Melbourne, Abstract. We describe the motivation, design and implementation of an infrastructure to support metadata quality assessment within a specialised Open Archives Initiative (OAI) sub-domain, the Open Language Archives Community (OLAC). While services for structural validation of metadata are widely used, there is little corresponding work regarding services which evaluate the semantic and syntactic content of metadata from a qualitative perspective. We posit that any measure of metadata quality benefits from both contextual and referential assessment - metadata on a per record and per collection basis is legitimately assessed against the baseline of broader community practice, as well as for compliance to any external standard. In this paper we describe the implementation of a metadata quality assessment scheme, and the corresponding interfaces to the evaluation tool. http://eprints.infodiv.unimelb.edu.au/archive/00001408/01/ICADL2004-PUBLISHED.pdf

22. Model: Open Language Archives Community • Metrics • code existence score, 0-1 (bonus for using controlled vocabulary) • element absence penalty, 0-1 (penalty for missing core elements) • per metadata record weighted aggregate, max 10 • archive level derivative metrics • archive diversity metric (use of controlled vocabulary across the archive) • metadata quality score metric (derived from individual scores) • core elements per record metric • core element usage metric • code usage metrics • code and element usage metrics • “star rating” (derived from average item score in archive) http://eprints.infodiv.unimelb.edu.au/archive/00001408/01/ICADL2004-PUBLISHED.pdf

23. Case Study: L'Année philologique • Log file provided by Professor Eric Rebillard, Director of Graduate Studies, Field of Classics • http://www.annee-philologique.com/aph/ • 126 OpenURLs in sample

26. Observations: log file scan [Log file is not available in Powerpoint version. Please contact Adam Chandler for more information]

27. log examples: 2000-2001 2000-2001 2000-2001 2004-2005 2004-2005 2003-2004 2004-2005 1998-1999 2004-2005 2004-2005 Observations: date Date of publication in ISO 8601 form YYYY, YYYY-MM or YYYY-MM-MM [p.56] NOTE: "chron" Indications of chronology in a non ISO8601 form (like "Spring" or "1st quarter") should be carried in this element; the element content is not normalized. Where numeric ISO8601 dates are also available, they should be provided in the "date" element. As such, a recorded date of publication of "Spring, 1992" becomes "date=1992" and "chron=spring". Chronology information can also be provided in the "ssn" and "quarter" elements [p. 57]

28. Observations: volume and issue log examples: N.%20S.%2055%20(1) 7%20(1) 43%20(3-4) N.%20S.%2055%20(2) 4a%20ser.%203%20(1) N%B0%20152 N%B0%2054 7%20(2) 133%20(2) 13-14 4a%20ser.%203%20(1) 31%20(1) 133%20(2) 38%20(3) 98%20(1) N.%20S.%2055%20(1) Volume is usually expressed as a number but could be roman numerals or non-numeric, e.g. "124", or "VI"."4“ [p.57] Issue: This is the designation of the published issue of a journal, corresponding to the actual physical piece in most cases. While usually numeric, it could be nonnumeric. Note that some publications use chronology in the place of enumeration, i.e. Spring, 1998. [p.58]

29. Observations: spage "spage=" is missing: more useful than pages field when linking to full text First page number of a start/end (spage-epage) pair. Note that pages are not always numeric [p.58]

30. Observations: missing ISSNs International Standard Serial Number (ISSN). ISSN numbers may contain a hyphen, e.g. "1041-5653" [p. 59] "ISSN=" these are easier to resolve than titles, especially with titles that contain special characters

31. Observations: character encoding Character encoding: Use UTF-8 Specify character encoding this way in OpenURl 1.0: info:ofi/enc:UTF-8 Source: http://alcme.oclc.org/openurl/servlet/OAIHandler?verb=ListRecords&metadataPrefix=oai_dc&set=Core:Character+Encodings

32. Observations: Missing WorldCat numbers Including OCLC WorldCat numbers would help to resolve title level ambiguities, especially when the request is routed to InterLibrary Loan Data from title matching in WorldCat 17 titles without an ISSN To do this means moving from OpenURL 0.1 to 1.0 format info:ofi/nam:info:oclcnum: Source:http://alcme.oclc.org/openurl/servlet/OAIHandler?verb=ListRecords&metadataPrefix=oai_dc&set=Core:Namespaces

33. Analysis of L'Année philologique in log sample that are held in WorldCat libraries Total titles analyzed: 81 Total confirmed held by Cornell in WorldCat: 53 (margin of error) Unconfirmed in or out of WorldCat: 6 Median number of libraries that hold these titles: 67 Thus, even if the metadata were perfect, finding the title through ILL, especially without an identifier (ISSN, ISBN, WorldCat) is expensive. Caveat: Not all of a library’s holdings are in WorldCat, especially journals.

34. The scale of the OpenURL quality problem Cornell link resolver activity: December 3, 2007 – February 8, 2008: 53,062 openurls were sent to link resolver.

35. Discussion

36. Notes and links http://library4.library.cornell.edu/openurl/index.html How many openurls came into Cornell dec – feb? http://www.language-archives.org/index.html http://www.niso.org/standards/standard_detail.cfm?std_id=783 http://erms.library.cornell.edu/webbridge/edit beforelinks.html