The SCI gave rise to multiple citation-based measures, with two, in particular, warranting mention. The first – another brainchild of Garfield’s – is impact factor (IF), which offers a putative indication of an academic journal’s quality based on the average number of times its articles were cited during the previous two years.
SCI催生了众多基于引用的指标，其中有两个特别值得注意。第一个也源于加菲尔德的构思，名为影响因子（impact factor，IF），该指标以所刊文章在前两年中平均被引用的次数为基础推定学术期刊的质量。高影响因子可以立竿见影地提高期刊的地位。