Humans seem to like metrics of all sorts, and we tend to develop and apply them also to subjects that do not naturally lend themselves to "objective measurement". George David Birkhoff wrote a book entitled Aesthetic Measure (1933) to develop a mathematical theory capable of measuring the aesthetic value of a piece of art. (See this nice little article to get an idea of the gist of Birkhoff's proposal.)
In our age in which "impact" and "leadership" are two of the main gods of academia, we are trying to do the G.D. Birkhoff and develop all kinds of metrics to determine how valuable our research is. The discussion of whether these metrics are any good at all, and whether they should be used in evaluating applicants for positions/promotion etc., would need a series of posts. Here I just want to point out one of these metrics.
Jorge Hirsch developed the h-number as a measure of the scientific output of a researcher. Being curious, many of us, including yours truly, will immediately try to determine (an approximation to) their h-number. This is now easy to do, thanks to a a script written by my BRICS colleague Michael I. Schwartzbach (University of Aarhus), which consults Google Scholar. Here is Michael's web interface.
According to Michael's script, my h-number is something like 14. This is far off from the h-number of people among the h-number elite maintained by Jens Palsberg (UCLA), but then again anything else would have been a major surprise to me.
Enjoy computing your h-number and those of your friends/competitors, but please resist the temptation of reading too much into this or any other metric.
[In case you are wondering where the title of this post comes from, I can tell you that it is based on the title of the second song in 3 Feet High and Rising, the debut album from American hip-hop trio De La Soul. In that song, "the magic number" was, guess what, three.]