Learning user preferences in online dating
Hence, the negative ratings indicate many useful information and thus should not be neglected or simply considered to be negative.
It consists of 943 users and 1682 movies, and discrete rating records from 1 star to 5 stars.
First, given a rating scale where the highest score denotes the most positive opinion and the lowest score indicates the most negative opinion, users’ rating scores do not distribute evenly along the whole rating scale .
Second, different users may have different rating criterions, some good-tempered users are willing to give high scores whereas other critical people seldom give full marks to any items they have watched .
Therefore, individual rating criterions may vary in different periods, depending on the previous items he has watched.
Besides, a user’s negative ratings may have a different temporal influence from his positive ratings on his future preference.
Last but not least, the negative ratings indicate dislike and simultaneously relevance, and they may play an either negative or positive role depending on the sparsity of training set and the popularity of the corresponding items .