On 9 Feb 2008, at 21:36, Arthur Sale wrote:
It looks as though the algorithm is the same as for
university websites.
Rank each repository for inward bound hyperlinks
(VISIBILITY)
Rank every repository for number of pages (SIZE)
Rank every repository for number of 'interesting'
documents eg .doc. .pdf (RICH FILES)
Rank every repository for number of records returned by a
Google Scholar search (GOOGLE SCHOLAR)
Compute (VISIBILITY x 50%) + (SIZE x 20%) + (RICH FILES x
15%) + (GOOGLE SCHOLAR x 15%)
And then rank the repositories on this score.
This is a poor measure in general. VISIBILITY (accounts
for 50% of score!) is not necessarily useful for
repositories, when harvesting in more important than
hyperlinks. It will be strongly influenced by staff
members linking their publications off a repository
search. Both SIZE and RICH FILES measure absolute size
and say nothing about currency or activity. Some of the
higher placed Australian universities have simply had old
stuff dumped in them, and are relatively inactive in
acquiring current material. Activity should be a major
factor in metrics for repositories, and this could easily
measured by a search limited to a year (eg 2007), or by
the way ROAR does it through OAI-PMH harvesting.
I believe that the Webometrics (ghastly name!) ranking of
repositories uses the same criteria as its ranking of universities ie
it is attempting to quantify the impact that the repository has had.
This is very different to the size, deposit activity, or even
used-ness of the repository and explains why the major contributing
factor is VISIBILITY. The main issue for this league table is "how
much evidence is there in the public web that your active research
and scholarly outputs are valued enough by your community of peers
that they are linking to them".
This will probably seem entirely arbitrary to some people, and
entirely obvious to others, depending on how much they see "the web"
as a para-literature. It mimics Google's PageRank valuation of web
pages according to how many 'votes' (links/quasi-citations) they get
from other pages from independent sources.
It is not possible to tell with any accuracy whether a University
Website is "a good website" simply by looking at the University's
place in the Webometrics Ranking of Universities. The website is
simply a channel which delivers visibility-impact for the University
(or not). Similarly for the repository.
--
Les Carr
Received on Sun Feb 10 2008 - 00:03:06 GMT