Percentiles are like quartiles, except that percentiles divide the set of data into 100 equal parts while quartiles divide the set of data into 4 equal parts.  Percentiles measure position from the bottom.

Percentiles are most often used for determining the relative standing of an individual in a population or the rank position of the individual.  Some of the most popular uses for percentiles are connected with test scores and graduation standings.  Percentile ranks are an easy way to convey an individual's standing at graduation relative to other graduates.  

若能收集到该词条相关资料的跟帖者给予奖励，根据收集资料的水平给予5～100不等的论坛币，当然也可以谈谈自己的看法、应用背景，相关软件知识，上传资料等等都可以。请大家尽量不要复制一些搜索引擎很容易收集到的资料。

     我每天都会发送不等数量的词条，所以诚邀不同统计背景的各路大侠给予评论。

     欢迎大家多多跟帖！要数量也要质量哟