Showing posts with label h-index. Show all posts
Showing posts with label h-index. Show all posts

Thursday, June 4, 2009

PLoS launches new campaign on Article Level Metrics (ALMS)

























As many of you are aware of, I am quite critical of the "Impact Factor"-hysteria when it comes to journals. It is very weird, I think, that an article's importance should be measured by where it was published. To be sure, there is a correlation between the Impact Factor (IF) of a journal, and the number of citations of the average article there (per definition), but the correlation across all articles is at most moderate (around 0.5, if I remember correctly).

This high variance means that many individual "low-impact"-papers are regularly published in "high-impact"-journals like Nature and Science. These papers receive few citations, many of them fewer citations than papers published in more specialist journals in our field such as Evolution or American Naturalist.

Clearly, something is wrong here. Should a person who is lucky to get a paper in to Nature, but which is not cited a lot, be offered a job or a research grant, while a competitor who have published a much more cited article in a "normal" journal not get the job? Clearly not, if you ask me. What should matter, ultimately, is the citation rate and importance of individual or articles or authors, not journals.

This is where I think scientific assesment will move in the future. We can think of, for instance, the increasing use of the "h-index" to evaluate individual scientists, which seems to replace the length of publication lists or the journals where people have published as a criterion to decide who are the "best" scientists. The general message should be: try to publish fewer, but better papers, because you will be evaluated as an individual and there are no shortcuts or easy ways of cheating these new measures.

Along these lines, the new and rapidly growing OA-journal PLoS ONE has just launched a campaing for Article Level Metrics (ALMS). The staff at PLoS ONE hopes that these new measures, which includes per-article performance measures such as citation rates, number of downloads, coverage in media and the bloggosphere, inlinks and other measures of "importance" will outcompete old-fashioned journal Impact Factors (IF:s). IF:s are increasingly subject to criticisms, and I would not hesitate to call them old-fashioned and yesterday's hat.

Just as the "h-index" quickly became popular and established itself as a new evaluation tool of individual scientists and their performance, ALMS will hopefully also contribute to deconstruct and remove the "monopoly" of IF:s and the naive use of them by hiring agencies. The journals that should worry most about this should be the traditional high-IF journals like Nature and Science. Their whole existence and high prestige has been built more or less solely on the absurd IF-system, and if starts cracking down, their future might be in jeopardy and they can certainly not take anything for granted. Here you can follow a "Webinar" where the Editor of PLoS ONE (Peter Binfield) explains more about ALMS.

Saturday, May 23, 2009

h-index! b-index!

Here is an article from wired.com that explain the h-index and its origin.  It’s a fun story and it's nice to know the basic formula of the h-index (h=n means you have published n articles that have been cited at least n times).

I’ve come up with a new metric, the b-index, which describes the impact of said blog.  Instead of times cited we are looking at times commented upon.   Our blog’s b-index is 6, explanation follows:

We have 32 posts so far with 23 comments going to a single post.  Stellar!  Ordering posts by high to low comment level we have the following sequence 23, 10, 8, 8, 7, 6, 6, 5, 5 etc.  Counting down the line we find that 6 posts have a comment level greater than or equal to six. 

Is that good?  Who knows!  But hey, it’s our index and we set the bar.