摘要
针对传统协同过滤推荐算法的稀疏性、扩展性问题,提出了结合似然关系模型和用户等级的协同过滤推荐算法.首先,定义了用户等级函数,采用基于用户等级的协同过滤方法,在不影响推荐质量的前提下有效提高了推荐效率,从而解决扩展性问题;然后,将其与似然关系模型相结合,使之能够综合利用用户信息、项目信息、用户对项目的评分数据,对不同用户给出不同的推荐策略,从而解决稀疏性问题,提高推荐质量.在MovieLens数据集上的实验结果表明,该算法比单纯使用基于似然关系模型或传统协同过滤技术的推荐算法,不仅推荐质量有所提高,推荐速度比传统协同过滤算法明显加快.
Collaborative filtering is one of successful technologies for building recommender systems. Unfortunately, it suffers from sparsity and scalability problems. To address these problems, a collaborative filtering recommendation algorithm combining probabilistic relational models and user grade （PRM-UG-CF） is presented. PRM-UG-CF has primary two parts. First, a user grade function is defined, and user grade based collaborative filtering method is used, which can find neighbors for the target user only in his near grade, and the number of candidate neighbors can be controlled by a parameter, so recommendation efficiency is increased and it solves the scalability problem. Second, in order to use various kinds of information for recommendation, user grade based collaborative filtering method is combined with probabilistic relational models （PRM）, thus it can integrate user information, item information and user-item rating data, and use adaptive strategies for different grade users, so recommendation quality is improved and it solves the sparsity problem. The experimental results on MovieLens data set show that the algorithm PRM-UG-CF has higher recommendation quality than a pure PRM-based or a pure collaborative filtering approach, and it also has much higher recommendation efficiency than a pure collaborative filtering approach.
出处
《计算机研究与发展》
EI
CSCD
北大核心
2008年第9期1463-1469,共7页
Journal of Computer Research and Development
基金
国家自然科学基金重大项目(60496321)
国家自然科学基金项目(60573073
60773099)
国家"八六三"高技术研究发展计划基金项目(2006AA10Z245
2006AA10A309)
吉林省科技发展计划基金项目(20030523)
欧盟项目(TH/Asia Link/010(111084))~~
关键词
推荐算法
协同过滤
似然关系模型
用户等级
平均绝对偏差
recommendation algorithm
collaborative filtering
probabilistic relational model
user grade
mean absolute error （MAE）
