New Ranking of Central and Institutional Repositories (fwd)
harnad at ECS.SOTON.AC.UK
Sat Feb 9 21:51:25 EST 2008
---------- Forwarded message ----------
Date: Sat, 9 Feb 2008 23:53:18 +0000
From: Leslie Carr <lac--ecs.soton.ac.uk>
Subject: Re: New Ranking of Central and Institutional Repositories
On 9 Feb 2008, at 21:36, Arthur Sale wrote:
> It looks as though the algorithm is the same as for university
> 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.
More information about the SIGMETRICS