Today marked two milestones related to my scientific career.  First, according to the Web of Knowledge, my ‘h-index‘ finally hit 12!  The h-index (Hirsch number) is a rough measure of both the productivity of a scientist and the impact of his/her research.  It is defined as:

A scientist has index h if h of his N_p papers have at least h citations each, and the other (N_p – h) papers have at most h citations each.

In my case, an h-index of 12 means that I have 12 papers which have been cited 12 or more times by other scientists.

Years ago, a scientist’s impact and productivity would be measured by the total number of citations their research received.  This could give a very misleading view of a scientist’s career: a scientist might get lucky and have one paper which has received a thousand citations, but never been able to capture the interest of researchers again.   The definition of the h-index prevents rewarding ‘one-hit wonderism’ in assessing a career.

I myself have, for the past year, had 11 papers with 12 or more citations, and three more with 11 citations each, tantalizingly close to an h-index of 12.  I should mention that the citation that pushed me over the top was not a self-citation!

The h-index obviously isn’t the last word on academic performance, but it is still nice to see it go up.  The number of citations my work has received each year has been steadily increasing, as well:

Although such statistics are highly enjoyable from a pure vanity point of view, they also will be one of the criteria that can influence my tenure decision.  Also, in planning future research/funding, it is helpful to see what aspect of my research is drawing the most interest.

I also note that the one-thousandth comment was posted on my blog today, by my fiancée:

McCain is a moron. ‘Nuff said.

I can’t think of a comment more worthy of the milestone!