Abstract: 'The use of citation counts to assess the impact of research articles is well established. However, the citation impact of an article can only be measured several years after it has been published. As research articles are increasingly accessed through the Web, the number of times an article is downloaded can be instantly recorded and counted. One would expect the number of times an article is read to be related both to the number of times it is cited and to how old the article is. This paper analyses how short-term Web usage impact predicts medium-term citation impact. The physics e-print archive -- arXiv.org -- is used to test this.'
Conclusion: 'Whereas the significance of citation impact is well established, access of research literature via the Web provides a new metric for measuring the impact of articles – Web download impact. Download impact is useful for at least two reasons: (1) The portion of download variance that is correlated with citation counts provides an early-days estimate of probable citation impact that can begin to be tracked from the instant an article is made Open Access and that already attains its maximum predictive power after 6 months. (2) The portion of download variance that is uncorrelated with citation counts provides a second, partly independent estimate of the impact of an article, sensitive to another form of research usage that is not reflected in citations (Kurtz 2004). This study found a significant and sizeable correlation of approximately 0.4 between the citation and download impact of articles in physics and mathematics. This was based on Web downloads from the UK arXiv.org mirror only, and on those citations that could be automatically found and linked by Citebase. The true correlation may in fact prove somewhat higher once more download sites are monitored and automatic linking becomes more accurate. It will no doubt vary from field to field, and may also change as the proportion of Open Access content (now 10-20%) approaches 100%.'
Posted by
Peter Suber at 3/05/2005 11:43:00 AM.
The open access movement:
Putting peer-reviewed scientific and scholarly literature
on the internet. Making it available free of charge and
free of most copyright and licensing restrictions.
Removing the barriers to serious research.
I recommend the OA tracking project (OATP) as the best way to stay on top of new OA developments. You can read the OATP feed on a blog-like web page or subscribe to it by RSS, email, or Twitter. You can also help build the feed by tagging new developments you encounter.
