1. 1 Chuck Koscher, CrossRef New Developments Relating to Linking Metadata Metadata Practices on the Cutting Edge May 20, 2004 Chuck Koscher Technology Director, CrossRef ckoscher@CrossRef.org

2. 2 Chuck Koscher, CrossRef CrossRef’s Mission  To provide services that bring the scholar to authoritative primary content, focusing on services that are best achieved through collective agreement by publishers – Journals – Books – Conference proceedings – Dissertations – Patents – Gray literature – Etc…

3. 3 Chuck Koscher, CrossRef CrossRef Indicators  307 participating publishers  290 libraries and consortia  33 agents and affiliates  11.1 million items, 9,500 journals  6 million DOI resolutions/month  >2.5 million DOIs retrieved per month  ~300,000 records updated per month  650,000 book and proceedings DOIs

4. 4 Chuck Koscher, CrossRef DOI links being ‘clicked’

5. 5 Chuck Koscher, CrossRef How DOIs & CrossRef Work Constant address of the Resolver DOI used to ‘lookup’ the entity’s URL Publisher of the target entity 1 1.Deposit article meta-data to CrossRef with the DOI & URL 2.Query CrossRef for the DOI using meta-data 3.Present the referring article to the user with reference links active as DOIs 4.The user clicks on a link 5.Their browser sends the link to the DOI Resolver 6.The Resolver finds the URL and re- directs the user to the target document HTTP://dx.doi.org/10.1016/S0040-4039(01)80789-9 Publisher of the referring entity 2 User 3 Referrer Source 4 Referent 5 6 Service Target

6. 6 Chuck Koscher, CrossRef CrossRef Developments  Main CrossRef developments:  DOI lookups are now free (costs shifted to the depositing publisher)  Article network via reference links has reached critical mass (DOIs are mainstream)  Forward Linking (cited-by links)  CrossRef Search Cross-publisher full text search  Multiple resolution (the next thing)

7. DOIs in Online Full Text

8. DOIs in Reference Citations

9. 9 Chuck Koscher, CrossRef DOIs as Article Locators

10. 10 Chuck Koscher, CrossRef Publish Ahead of Print

11. 11 Chuck Koscher, CrossRef Forward Linking  Many publishers/hosting platforms offer this service now but only for intra-site references. CrossRef extends the reach to inter-site/inter-publisher.  Publishers deposit the list of references in the article  An opt-in service available to CrossRef members  A new query to get the list of articles that cite a target article  Alerts will be sent when a new article is deposited that cites the target

12. 12 Chuck Koscher, CrossRef Forward Linking

13. 13 Chuck Koscher, CrossRef CrossRef Search powered by Google  CrossRef Search Pilot  Cross-disciplinary, full text search of journals and conference proceedings  Normal Google search with results limited to authoritative scholarly content  Content also available in regular Google searches

14. 14 Chuck Koscher, CrossRef CrossRef Search cont’d  Publishers have CrossRef Search boxes on their normal search pages  Pilot to run through end of 2004  Evaluation of functionality, ranking, end user feedback  DOIs used for indexing articles and linking from search results back to publisher  Optional for CrossRef members – participation in Pilot to be expanded in 2004

15. 15 Chuck Koscher, CrossRef

16. 16 Chuck Koscher, CrossRef

17. 17 Chuck Koscher, CrossRef

18. 18 Chuck Koscher, CrossRef Multiple Resolution  The user makes a choice

19. 19 Chuck Koscher, CrossRef Multiple Resolution The Link Text … <script src="http://www.crossref.org/MRServlet/MR/10.5555/sample-doi? The%20Link%20Text"> Single resolution link: Multiple resolution link:  Construction of a ‘normal’ link Vs a multiple resolution link

20. 20 Chuck Koscher, CrossRef Multiple Resolution  Management of the underlying metadata DOI => One URL, that being the location of the article at the publisher’s site (default format) DOI => URL of the article at the publisher’s site (default format, e.g. HTML) + URL of the article in other formats (Word, PDF, text..) + URLs of related links (journal home page, supporting data … etc) + URLs of other locations of the article (institutional repositories) + URL of services (rights procurement, document print..) Single resolution link: Multiple resolution link:

21. 21 Chuck Koscher, CrossRef Multiple Resolution  How will it work?  CrossRef will define the framework (menu taxonomy, policies, tools, procedures)  Target content owners will decide what they want on the menus of their items (third parties must work with the content owner to get their interests included in a menu)  Source content owners agree to use multiple resolution style links (the menu content is not controlled by the owner of the link, its controlled by the target of the link)

22. 22 Chuck Koscher, CrossRef OpenURL and DOIs/CrossRef  CrossRef helps solve the appropriate copy problem by providing a ‘reverse’ DOI lookup (DOI in / meta-data out) http://doi.crossref.org/servlet/query? id=10.1006/jmbi.2000.4282&pid= :  CrossRef offers an OpenURL 1.0 compliant resolver http://doi.crossref.org/resolve?pid= : &aulast=Maas &title= JOURNAL OF PHYSICAL OCEANOGRAPHY &volume=32&issue=3 &spage=870&date=2002 (This resolver will redirect you to the target document) OpenURL and DOI are complementary technologies

23. 23 Chuck Koscher, CrossRef Metadata – Lessons learned  What does linking with metadata and the movie The Matrix have in common?  People Vs. the machines  But what about standards?  Standards do not address semantics  Real world users can break anything!  Help me mister wizard?  Parsers catch <50% of the problems, lots of ‘utility’ programs  Big drivers: Policy, governance, existing practice  Collect more than you need, you’ll figure out a use for it later  History is important, keep track of it!

24. 24 Chuck Koscher, CrossRef IDF Metadata Interoperability indecs Data Dictionary (iDD)  CrossRef is a registration agency (one of nine globally) for the International DOI Foundation  The IDF’s mission is to promote and oversee the use of the DOI as a universal identifier (ANSI/NISO Z39.84-2000 )  As an identifier the DOI is powerful because of the underlying metadata system  A scaleable distributed registry

25. 25 Chuck Koscher, CrossRef IDF Metadata Interoperability indecs Data Dictionary (iDD)  Each RA operates in specific sectors  They have their own metadata schema  Through policy the IDF promotes inter-RA operability  Definition of a kernel metadata set common to any DOI regardless of sector applicability  Construction of common tools (API) to access the registry  Construction of a cross-schema map, the iDD

26. 26 Chuck Koscher, CrossRef IDF Metadata Interoperability indecs Data Dictionary (iDD)  The iDD is fully developed and is undergoing trials  What does the iDD do?  A schema is input to the iDD by mapping its terms to a structured ontology  Metadata interoperability devices (exchange schemas) are drawn from the iDD http://www.doi.org/factsheets/DOIDataDictionaries.html Metadata interoperability means enabling information that originates in one context to be used in another in as automated a way as possible

27. 27 Chuck Koscher, CrossRef Chuck Koscher Technology Director, CrossRef ckoscher@CrossRef.org WWW.CROSSREF.ORG