Van Noorden R. Metrics: a profusion of measures. Nature 2010; 465:864-866
Within the past decade, the development of scientific performance indicators has accelerated rapidly, accompanied by the the ready availability of online databases such as the Web of Science, Scopus and Google Scholar. The author offers a survey of this evolving situation: from the impact factor to the h-index and its more than a dozen variants and to the increasingly popular class of measure called "evaluative informetric". This last metric gives heavier weight to citations from papers that are themselved highly cited.