To personalize or not

Weinan Zhang, Jun Wang, Bowei Chen, Xiaoxue Zhao
2013 Proceedings of the 7th ACM conference on Recommender systems - RecSys '13  
Personalization techniques have been widely adopted in many recommender systems. However, experiments on real-world datasets show that for some users in certain contexts, personalized recommendations do not necessarily perform better than recommendations that rely purely on popularity. Broadly, this can be interpreted by the fact that the parameters of a personalization model are usually estimated from sparse data; the resulting personalized prediction, despite of its low bias, is often
more » ... . In this paper, we study the problem further by investigating into the ranking of recommendation lists. From a risk management and portfolio retrieval perspective, there is no difference between the popularity-based and the personalized ranking as both of the recommendation outputs can be represented as the trade-off between expected relevance (reward) and associated uncertainty (risk). Through our analysis, we discover common scenarios and provide a technique to predict whether personalization will fail. Besides the theoretical understanding, our experimental results show that the resulting switch algorithm, which decides whether or not to personalize, outperforms the mainstream recommendation algorithms.
doi:10.1145/2507157.2507167 dblp:conf/recsys/ZhangWCZ13 fatcat:be33yyzfqrfbffmv3oqdkech44