Multi-Objective Recommender Systems (MORSs) emerged as a paradigm to guarantee multiple (often conflicting) goals. Besides accuracy, a MORS can operate at the global level, where additional beyond-accuracy goals are met for the system as a whole, or at the individual level, meaning that the recommendations are tailored to the needs of each user. The state-of-the-art MORSs either operate at the global or individual level, without assuming the co-existence of the two perspectives. In this study, we show that when global and individual objectives co-exist, MORSs are not able to meet both types of goals. To overcome this issue, we present an approach that regulates the recommendation lists so as to guarantee both global and individual perspectives, while preserving its effectiveness. Specifically, as individual perspective, we tackle genre calibration and, as global perspective, provider fairness. We validate our approach on two real-world datasets, publicly released with this paper.

多目标推荐系统通过在全局或个体层面操作，旨在同时满足多个目标，然而当全局和个体目标共存时，现有的系统无法同时满足两类目标。本研究针对这一问题，提出了一种调节推荐列表的方法，以保证全局和个体视角的有效性，并对两个真实数据集进行了验证。

MOReGIn：全局与个体的多目标推荐