把f指数放大100倍取对数后再放大100倍定义为对数f指数fl:。作为一种可以普遍应用的学术排序参数,f指数是优秀的象征——具有f指数的团体和个人都相对优秀,而对数f指数fl可使区分度更细化——fl≥200表征非常优秀,fl=100-200表征比较优秀,fl≤100表征相对而言不够优秀。
Logarithmic f-index fl is defined as , which can reach more differentiation while f-index marks excellence, fl ≥ 200 means very excellence and fl = 100-200 excellence, while fl ≤ 100 means poor relatively.