A physicist, Jorge Hirsch, devised a formula to determine the quality of scientific papers published by a scientist. “The h-index is the number n of a researcher’s papers that have been cited by other papers at least n times. High numbers = important science = important scientist.” According to Wired, June 2009 at 94, “similar statistical approaches have become standard practice in Internet search algorithms and on social networking sites.
Legal departments could translate this idea into the number of matters for which a law firm was hired. Let me explain. Law firm One has been retained during the past three years 100 times. Law firm Two has been retained for 50 matters, while law firm Three has handled 25 matters. Down the list, law firm Twelve has been retained 12 times. Thus the number 12 (“n”) law firm has been retained by your department at least 12 (“n”) times. Your “h[law firm]-index” is 12. Every legal department can figure out its own h[law firm]-index and, if that information is shared, compare their measure of concentration of outsourced work. The lower the number, the more concentrated the work.
The index is a descriptive metric for concentration of work given to your firms. An employment firm may top the list if it handles many smallish matters. Or a patent boutique may if it handles many patents. But eventually, down the list a ways, some firm will hit the h[law firm]-index point.