论文标题
部分可观测时空混沌系统的无模型预测
The Unfairness of Popularity Bias in Book Recommendation
论文作者
论文摘要
最近的研究表明,建议系统通常遭受流行偏见。受欢迎程度偏见是指经常建议流行项目(即经常评级的项目)的问题,而建议很少或根本不建议使用较少受欢迎的项目。研究人员采用了两种方法来检查受欢迎程度的偏见:(i)从用户的角度来分析建议系统与用户在接收流行物品方面的期望偏离多远,以及(ii)通过分析长尾物品所获得的暴露量,通过整体目录的覆盖范围和新颖性来衡量。在本文中,我们检查了书籍域中的第一个观点,尽管这些发现也可以应用于其他领域。为此,我们分析了众所周知的书本数据集,并根据他们对流行项目的趋势(即,利基,多样,以畅销书为中心)来定义三个用户组。此外,我们从准确性(例如NDCG,Precision,Recell)和受欢迎程度偏见的观点中评估了九种最先进的建议算法和两个基准(即随机,大多数)的性能。我们的结果表明,大多数最先进的推荐算法都遭受了书籍域的流行偏见,并且尽管概况尺寸较大,但仍无法满足用户的利基市场和多样化口味的期望。相反,以公平性和个性化的方式,以畅销书为重点的用户更有可能收到高质量的建议。此外,我们的研究表明,对于属于多元化和畅销书群体的用户的推荐算法中的个性化与不公平性偏见之间的折衷,即具有个性化的算法具有很高的个性化能力,因此受欢迎程度偏见不公平。
Recent studies have shown that recommendation systems commonly suffer from popularity bias. Popularity bias refers to the problem that popular items (i.e., frequently rated items) are recommended frequently while less popular items are recommended rarely or not at all. Researchers adopted two approaches to examining popularity bias: (i) from the users' perspective, by analyzing how far a recommendation system deviates from user's expectations in receiving popular items, and (ii) by analyzing the amount of exposure that long-tail items receive, measured by overall catalog coverage and novelty. In this paper, we examine the first point of view in the book domain, although the findings may be applied to other domains as well. To this end, we analyze the well-known Book-Crossing dataset and define three user groups based on their tendency towards popular items (i.e., Niche, Diverse, Bestseller-focused). Further, we evaluate the performance of nine state-of-the-art recommendation algorithms and two baselines (i.e., Random, MostPop) from both the accuracy (e.g., NDCG, Precision, Recall) and popularity bias perspectives. Our results indicate that most state-of-the-art recommendation algorithms suffer from popularity bias in the book domain, and fail to meet users' expectations with Niche and Diverse tastes despite having a larger profile size. Conversely, Bestseller-focused users are more likely to receive high-quality recommendations, both in terms of fairness and personalization. Furthermore, our study shows a tradeoff between personalization and unfairness of popularity bias in recommendation algorithms for users belonging to the Diverse and Bestseller groups, that is, algorithms with high capability of personalization suffer from the unfairness of popularity bias.