信息检索与数据挖掘 2019/3/315 SIGIR 2018 Best Paper Should I Follow the Crowd?A Probabilistic Analysis of the Effectiveness of Popularity in Recommender Systems The use of IR methodology in the evaluation of recommender systems has become common practice in recent years.IR metrics have been found however to be strongly biased towards rewarding algorithms that recommend popular......The fundamental question remains open though whether popularity is really a bias we should avoid or not;whether it could be a useful and reliable signal in recommendation,or it may be unfairly rewarded by the experimental biases.......We build a crowdsourced dataset devoid of the usual biases MovieLens 1M Netflix 0.3 □ Random recommendation Popularity(nr.positive ratings) 0.2 ▣Average rating User-based kNN 01 Item-based kNN 0 Matrix factorization Figure 1:Typical offline experimental results for non-per- sonalized popularity-based recommendation compared to personalized algorithms on two public datasets.信息检索与数据挖掘 2019/3/31 5 SIGIR 2018 Best Paper Should I Follow the Crowd? A Probabilistic Analysis of the Effectiveness of Popularity in Recommender Systems The use of IR methodology in the evaluation of recommender systems has become common practice in recent years. IR metrics have been found however to be strongly biased towards rewarding algorithms that recommend popular …... The fundamental question remains open though whether popularity is really a bias we should avoid or not; whether it could be a useful and reliable signal in recommendation, or it may be unfairly rewarded by the experimental biases. …... We build a crowdsourced dataset devoid of the usual biases ……