Integrated data like EFF, PER, such linear equations are mainly applied in ranking systems, not explaining concrete examples, which would be more explicit if be illuminated with simplified data.

• 象EFF、PER那样的线型方程式的综合性数据主要功用还是拿来做排名系统，它们实际说明问题的能力反而还不如简单处理的数据。