基于此网址,我发现Bayesian Rating,它很好地解释了评级模型,我想总结一下这个公式,使任何人实现SQL语句都更容易。如果我总结这样的公式,这会是正确的吗?
avg_num_votes = Sum(votes)/Count(votes) * Count(votes)
avg_rating = sum(votes)/count(votes)
this_num_votes = count(votes)
this_rating = Positive_votes - Negative_votes
加特
答案 0 :(得分:7)
看起来更像是这样:
avg_num_votes = Count(votes)/Count(items with at least 1 vote)
avg_rating = Sum(votes)/Count(items with at least 1 vote)
this_num_votes = Count(votes for this item)
this_rating = Sum(votes for this item)/Count(votes for this item)
如果您使用简单的+/-系统,Sum(votes) = Count(positive votes)
(即将+视为1, - 视为0)
另请参阅:Bayesian average。
答案 1 :(得分:0)
avg_rating不应该是:
萨姆(票)/计数(票)
伊夫