5星贝叶斯评级回报百分比

Question

我建立5星评级系统。问题来自用户对照片评分并最终 br 将返回超过100％，我怎样才能确保它以百分比回报并且不超过100％

br = ( (avg_num_votes * avg_rating) + (this_num_votes * this_rating) ) / (avg_num_votes + this_num_votes)

Answer 1

假设avg_rating和this_rating都不超过100％，并且所有值都是非负数，那么您的公式永远不会超过100％。

br = ( (avg_n * avg_r) + (this_n * this_r) ) / (avg_n + this_n) <=
   <= ( (avg_n * 100%) + (this_n * 100%) ) / (avg_n + this_n) =
   = 100% * (avg_n + this_n) / (avg_n + this_n) =
   = 100%

如果avg_rating和this_rating未按百分比衡量（例如，它们是星数0-5），则应首先将它们转换为百分比。