6th International Conference on Social Science Methodology, Amsterdam, 2004
Searching and browsing multiple subject gateways in the Renardus Service
Michael DayUKOLN, University of Bath
RC33 6th International Conference on Social Science Methodology,
Amsterdam, The Netherlands, 16-20 August 2004
http://www.ukoln.ac.uk/
6th International Conference on Social Science Methodology, Amsterdam, 2004
Outline
• Subject gateways
• The Renardus Service– Cross-searching– Cross-browsing
• Issues
• Future potential
6th International Conference on Social Science Methodology, Amsterdam, 2004
What are subject gateways? (1)
• Discovery services that give access to high-quality Web resources:– Selective (published criteria)– Typically based on resource description
(metadata)– Provides users with search and browse facilities– Use subject classification systems for subject
browsing
6th International Conference on Social Science Methodology, Amsterdam, 2004
What are subject gateways? (2)
• An example:– Resource Discovery Network (UK)– Includes the Social Science Information
Gateway (SOSIG)– Pioneer of the subject gateway concept– Now a mature service (>25K resources) run by
the Institute of Learning and Research Technology (ILRT) at the University of Bristol
– http://www.sosig.ac.uk/
6th International Conference on Social Science Methodology, Amsterdam, 2004
RDN Social ScienceInformation Gateway(August 2004)
http://www.sosig.ac.uk/
6th International Conference on Social Science Methodology, Amsterdam, 2004
What is the Renardus Service?
– A broker service that integrates access to European subject gateways (all subjects)
– Developed by a research project funded 2000-2002 by the European Commission as part of its Information Society Technologies (IST) programme
– Since 2002, managed by participating gateways through the Renardus Consortium
– Operational service hosted by the Goettingen State and University Library (SUB)
– http://www.renardus.org/
6th International Conference on Social Science Methodology, Amsterdam, 2004
Services participating in Renardus
DAINet - German Agricultural Information Network
DE
Denmark's Electronic Research Library (DEF) DK
DutchESS - Dutch Electronic Subject Service NL
Finnish Virtual Library (FVL), NOVAGate FI
Online dissertations (Die Deutsche Bibliothek) DE
Resource Discovery Network (RDN) UK
SSGFI gateways at SUB Goettingen (Anglistik Guide, Geo-Guide, History Guide, MathGuide)
DE
6th International Conference on Social Science Methodology, Amsterdam, 2004
Cross-searching
• Searches across all participating services:– Uses the Z39.50 protocol– Services provide metadata that conforms to the
Renardus "application profile":• Based on the Dublin Core Metadata Element
Set (DCMES)• Added element: Country (of origin)• Mandatory elements:Identifier, Title,
Description, Subject, …
6th International Conference on Social Science Methodology, Amsterdam, 2004
Cross-browsing (1)
• Renardus needed to provide subject browse access across all services– Subject gateways use many different subject
schemes for browsing• Some 'home-grown'• Others based on (or adapted from)
standards (e.g., DDC, LCC, UDC, MSC, Nederlandse Basisclassificatie)
– Also some variation in the depth of browsing structure (between 1 and 5 levels), although most are shallow
6th International Conference on Social Science Methodology, Amsterdam, 2004
Cross-browsing (2)
• Renardus chose to map local schemes to a universal classification scheme - the Dewey Decimal Classification (DDC):– Available online (WebDewey)– Covers all subjects, is frequently updated, has
global use, etc.– The project negotiated a research license from
OCLC Forest Press
6th International Conference on Social Science Methodology, Amsterdam, 2004
Classification mapping (1)
• General approach:– Mapping to local browse system, not to
individual resources– The mapping is one-way only, from the DDC to
the local browsing system– Mappings move from top levels of browse
structures before moving progressively down it
6th International Conference on Social Science Methodology, Amsterdam, 2004
Classification mapping (2)
• Mapping relationships:– Simple equivalence between terms not
expected– Five mapping relationships
• Fully equivalent• Narrower equivalent• Broader equivalent• Major overlap• Minor overlap
6th International Conference on Social Science Methodology, Amsterdam, 2004
Classification mapping (3)
• Syntax: LN (Local classification notation)
LC (Local classification caption)RL (Relationship code, i.e. =, >, <, MJ, or MN)DN (DDC notation)DC (DDC caption)UR (Local browsing URL for the class)NT (Notes):RE: (Record end)
6th International Conference on Social Science Methodology, Amsterdam, 2004
Classification mapping (4)
• Technical solutions:– Mapping tool developed by the German
CARMEN project (CarmenX)– Participating gateways provide a machine-
readable version of the classification scheme in use
– The tool (together with WebDewey) facilitates the production of the mapping information in the correct syntax
6th International Conference on Social Science Methodology, Amsterdam, 2004[Renardus Mapping Tool]
6th International Conference on Social Science Methodology, Amsterdam, 2004
Using the mapping information
• In Renardus, the DDC mapping information provides:– The basis of the cross-browse feature– Information for the advanced search feature,
e.g. search by DDC Classification
• The DDC browse structure forms the core part of the Renardus Service Web page
[Next slide …]
6th International Conference on Social Science Methodology, Amsterdam, 2004
6th International Conference on Social Science Methodology, Amsterdam, 2004
Cross-browsing in Renardus
• Based on a two-step process– first browsing within the DDC structure on the Renardus
Web pages– Then linking directly to the browse structures in local
gateways– Called "Browse and jump"
• Interface issues– Visual inconsistency– No clear path back to Renardus from the local gateways
6th International Conference on Social Science Methodology, Amsterdam, 2004
Navigational support
• Need for additional navigational support in large browsing structures
• Renardus developed some experimental features:– Searching for a different start page– Graphical navigation overview– Merge
6th International Conference on Social Science Methodology, Amsterdam, 2004
[Graphical Navigation Overview]
6th International Conference on Social Science Methodology, Amsterdam, 2004
Issues
• Sustainability– EU-funded project, no significant funding to
develop the service further
• Technology developments– Renardus cross-search currently based on
Z39.50– New distributed search technologies now
available:• SRW Search/Retrieve Web Service• OAI-PMH - already used for cross-searching
within the RDN
6th International Conference on Social Science Methodology, Amsterdam, 2004
Future potential (1)
• Multilinguality– Because DDC has been translated into many languages, it
is possible to add other language versions of the browse system into Renardus
• Automatic classification support for the mapping process– Managing the mapping information is a big commitment for
participating services
• Terminology services– Web services that combine knowledge organisation
systems and vocabularies - could replace custom-built mappings in Renardus
6th International Conference on Social Science Methodology, Amsterdam, 2004
Future potential (2)
• Web archiving initiatives– Not just describing Web resources, but collecting them
for future use (long term preservation)– Two main approaches to collection:
• Selective approach– Selection, negotiation of rights, harvesting
– Used by some national libraries and archives, also for special collections (e.g. political parties, elections)
• Automatic harvesting approach– Robot-based
– Used by the Internet Archive, some national libraries, etc.
6th International Conference on Social Science Methodology, Amsterdam, 2004
Future potential (3)
• Web-archiving (continued)– The selective approach has some commonality
with current subject gateway practice• e.g., The need for selection criteria and
descriptive metadata– This may be a possible area for collaboration in
the future … and of interest to social scientists
6th International Conference on Social Science Methodology, Amsterdam, 2004
Further information:
• Renardus Service: http://www.renardus.org/
• Social Science Information Gateway: http://www.sosig.ac.uk/
• UKOLN:http://www.ukoln.ac.uk/
Thank-you for your attention!
Examples
1. Simple and advanced searching
6th International Conference on Social Science Methodology, Amsterdam, 2004
Search example
• Simple search for "palaeontology"– Renardus searches each participating gateway using the
Z39.50 protocol– Retrieves hits from multiple gateways:
• RDN (129)• Geo-Guide (123)• NOVAGate (2)• DutchESS (1)• FVL (1)
– Displays results (detailed or brief)
6th International Conference on Social Science Methodology, Amsterdam, 2004
6th International Conference on Social Science Methodology, Amsterdam, 2004
6th International Conference on Social Science Methodology, Amsterdam, 2004
Linking to resources
– The results display the URL of the described resource as a hyperlink
– Users can also refer to the richer metadata record provided by the participating gateway
– The level of detail varies …– Examples from DutchESS and RDN (Biome)
follow …
[Next two slides …]
6th International Conference on Social Science Methodology, Amsterdam, 2004[Record from participating gateway (DutchESS)]
6th International Conference on Social Science Methodology, Amsterdam, 2004[Record from participating gateway (RDN Biome)]
6th International Conference on Social Science Methodology, Amsterdam, 2004
Advanced searching (1)
• Search options– Simple Boolean AND/OR searching on the
content of individual elements• Title, Subject, Description, Creator, DDC
Classification, Document Type– Term selection help
• For the elements: Title, DDC Classification, Subject and Type, a "term selection window" opens in some browsers to indicate terms that are already included in gateway indexes
6th International Conference on Social Science Methodology, Amsterdam, 2004
6th International Conference on Social Science Methodology, Amsterdam, 2004
Advanced searching (2)
• Other options:– Limit (filter) search by Document Type,
Language, or Country– Display options and search timeout– Select which gateways to search
6th International Conference on Social Science Methodology, Amsterdam, 2004
Browsing example (1)
• Browsing for information on 'mineralogy':– Select "science" in first browse level
• Note broader equivalent mapping to "Technology and Natural Sciences" (DEF)
– Then select "chemistry" …• Again, note narrower and broader
equivalents …[Next three slides …]
Examples
2. Cross-browsing
6th International Conference on Social Science Methodology, Amsterdam, 2004
6th International Conference on Social Science Methodology, Amsterdam, 2004
6th International Conference on Social Science Methodology, Amsterdam, 2004
6th International Conference on Social Science Methodology, Amsterdam, 2004
Browsing example (2)
– Then select "mineralogy"• Fully equivalent to "Mineralogy: General" in
GOK (Geo-Guide), "Mineralogy" in FVL• A narrower equivalent is "Mineral
paragenesis" in GOK (Geo-Guide)• Major overlap with "Mineralogie, Boden-,
Gesteins- und Lagerstättenkunde" in DDB online dissertations
[Next slide …]
6th International Conference on Social Science Methodology, Amsterdam, 2004
6th International Conference on Social Science Methodology, Amsterdam, 2004
Browsing example (3)
– Selecting the link takes the user to the relevant part of the browse hierarchy in the local gateway
– This is known as "browse and jump"– Examples of the relevant local browse
hierarchies in FVL and DDB online dissertations follow …
[Next two slides …]
6th International Conference on Social Science Methodology, Amsterdam, 2004[Finnish Virtual Library]
6th International Conference on Social Science Methodology, Amsterdam, 2004[DDB]
Additional information on navigation support features in Renardus cross-
browsing
6th International Conference on Social Science Methodology, Amsterdam, 2004
Navigational support (1)
• Need for additional navigational support in large browsing structures
• Renardus developed some experimental features:– Searching for an start page– Graphical navigation overview– Merge
6th International Conference on Social Science Methodology, Amsterdam, 2004
Navigational support (2)
– Finding a different start-page• It is possible to find a different page in the
browse structure, by entering a term in the search box available on each browsing page
• This takes you to a results page that links to the HTML and graphical overview versions of the Renardus browse hierarchy
[Next three slides …]
6th International Conference on Social Science Methodology, Amsterdam, 2004
6th International Conference on Social Science Methodology, Amsterdam, 2004
6th International Conference on Social Science Methodology, Amsterdam, 2004
6th International Conference on Social Science Methodology, Amsterdam, 2004
Navigational support (3)
– Graphical Navigation Overview• Gives a 'fisheye' view of the DDC browse
hierarchy• Allows users to see the browse term
(highlighted in red) together with related terms in surrounding classes
• Terms with content (highlighted in blue) link to the relevant page in the Renardus browse hierarchy
[Next slide …]
6th International Conference on Social Science Methodology, Amsterdam, 2004
6th International Conference on Social Science Methodology, Amsterdam, 2004
Navigational support (3)
• Merge– A short cut to viewing individual resource
descriptions from all related collections– Similar to "DDC Classification" search in
advanced search feature
[Next two slides …]
6th International Conference on Social Science Methodology, Amsterdam, 2004
6th International Conference on Social Science Methodology, Amsterdam, 2004