Information Technology Reference
In-Depth Information
Pre-harvested search - the true one-stop shop?
The second major approach to federated search is to harvest all of the
relevant sources of data, normalize them into a single metadata schema,
and index all of them together in one large union index. This approach
offers huge advantages in speed and in the logic that can be applied to
the presentation and sorting of results.
(Gibson, Goddard and Gordon, 2009)
Since January 2009 a number of products have been announced for beta
or open beta testing, the big three being Serials Solutions' Summon
Service,
20
Ex-Libris' Primo
21
and OCLC's Worldcat Local.
22
These products
intend to move a step beyond traditional federated search products in
creating a union index solution by harvesting content. They present a
new generation of resource discovery by attempting to provide the best
bits of federated search while eliminating the downside:
Single search
: a Google-like search box.
Relevancy ranking
: by using open-source algorithms such as Lucene,
these products rank results so that relevant results, rather than the
results from the quickest database, appear at the top; this provides
quality of search results, rather than the quantity of a Google
search.
Hosting
: these services offer hosted support on centralized servers.
Integration
: open APIs are used in order to integrate the products with
existing library systems or next-generation catalogues such as
VuFind, etc.
Clustering and faceting
: these features are easier to implement with a
hosted union index.
Full text and peer review
: results can be limited to full-text and/or
peer-reviewed content only, finally allowing fast full-text scholarly
results to be displayed for the user.
'Did you mean' suggestions
: guidance for alternative spellings,
misspellings and results with low hits.
Union Index
The harvested data does not only cover A&I databases; the library
