mahout用户推荐的工作原理如何？

Question

我使用mahout taste api的基于通用用户的推荐器来生成推荐..

我知道它建议根据给过去用户的评分......我没有得到推荐项目选择的数学......例如..

用户ID 58

itemid评级

 231 5

 235 5.5

 245 5.88

3个邻居，其中itemid和等级为{231 4,254 5,262 2,226 5}

{235 3,245 4,262 3} {226 4,262 3} 它建议我怎么做？

提前谢谢，

Answer 1

这取决于您为推荐人选择的UserSimilarity和UserNeighborhood。但一般来说，该算法对用户 u ：

的工作方式如下

for every other user w
    compute a similarity s between u and w
    retain the top users, ranked by similarity, as a neighborhood n
for every item i that some user in n has a preference for, but that u has no preference for yet
    for every other user v in n that has a preference for i
        compute a similarity s between u and v
        incorporate v's preference for i, weighted by s, into a running average

来源：Mahout in Action http://manning.com/owen/