Check out an article in The Wall Street Journal (6 June 2006) on the dubious methods using by science journals publishers to manipulate their impact factors rankings.
“Conceived 40 years ago, impact factors are essentially a grading system of how important the papers a journal publishes are. “Importance” is measured by how many other papers cite it, indicating that the discoveries, methodologies or insights it describes are advancing science.
Impact factors are calculated annually for some 5,900 science journals by Thomson Scientific, part of the Thomson Corp., of Stamford, Conn. Numbers less than 2 are considered low. Top journals, such as the Journal of the American Medical Association, score in the double digits. Researchers and editors say manipulating the score is more common among smaller, newer journals, which struggle for visibility against more established rivals…
Impact factors matter to publishers’ bottom lines because librarians rely on them to make purchasing decisions. Annual subscriptions to some journals can cost upwards of $10,000 (US).”
The full text of the article Science Journals Artfully Try To Boost Their Rankings is available here.