Investigating group recommendation techniques for multi-criteria settings.
Some techniques for generating recommendations to groups can be adopted in
multi-criteria rating settings. According to [31], a group preference model can be
built by aggregating the diverse preferences of several users. Similarly, a user’s preference for an item in multi-criteria rating settings can be predicted by aggregating
the preferences based on different rating criteria. More specifically, there can be
many different goals for aggregating individual preferences [55, 63], such as maximizing average user satisfaction, minimizing misery (i.e., high user dissatisfaction),
and providing a certain level of fairness (e.g., low variance with the same average
user satisfaction). Multi-criteria rating recommenders could investigate the adoption
of some of these approaches for aggregating preferences from multiple criteria.
Developing new MCDM modeling approaches. From the MCDM perspective,
the recommendation problem is posing novel challenges to the decision modellers.
On the one hand, there is a plethora of additional techniques that can be readily
adopted and used in such systems, such as including a sensitivity analysis step in
the algorithm, as [68] proposes. On the other hand, some studies indicate that recommendation is not a single decision making problem, since there are several decision problems that have to be addressed simultaneously, and each individual has
an influence on the recommendation provided to other individuals [54]. Neither it is
considered to be a typical group decision making problem nor a negotiation between
individuals [66]. Therefore, new MCDM modelling approaches should be proposed
and tested for multi-criteria recommendations [20].