Socially-Aware Recommender Systems Mitigate Opinion Clusterization
Lukas Schüepp, Carmen Amo Alonso, Florian Dörfler, Giulia De Pasquale
TL;DR
The paper tackles the challenge of opinion polarization and filter bubbles in recommender systems by introducing a socially-aware RS that leverages users' social network structure. It formulates a dynamic, multi-agent model based on a multi-topic Friedkin–Johnsen framework to capture the evolving opinions of users and creators under RS interactions, with a $d$-hop social influence mechanism guiding recommendations. Key contributions include the formalization of satisfaction and clusterization metrics within this dynamic setting, the proposal of a socially-aware RS that mimics social networks through $d$-hop neighborhood averages, and theoretical and empirical demonstrations that incorporating social structure can mitigate clusterization while balancing personalization. The findings suggest practical design principles for RS in real-world platforms to reduce polarization and echo-chamber effects without sacrificing user engagement, supported by synthetic and real-network experiments. Let $\text{sat}(u_i^T,c_j) = -\dfrac{1}{T}\sum_{t=0}^{T-1} \|u_i^t - c_j^t\|_2$ and $\text{cl}(\mathcal{U}^t) = \dfrac{1}{N}\sum_i s(u_i^t)$ with $s(u_i^t)$ the silhouette, and $r_i^t = r(u_i^t)$ guiding the RS via $c_j^t \sim \mathcal{R}(u_i^t)$. The approach demonstrates that music to policy can be found by balancing local personalization against global opinion diversity through network-aware control of recommendations.
Abstract
Recommender systems shape online interactions by matching users with creators content to maximize engagement. Creators, in turn, adapt their content to align with users preferences and enhance their popularity. At the same time, users preferences evolve under the influence of both suggested content from the recommender system and content shared within their social circles. This feedback loop generates a complex interplay between users, creators, and recommender algorithms, which is the key cause of filter bubbles and opinion polarization. We develop a social network-aware recommender system that explicitly accounts for this user-creators feedback interaction and strategically exploits the topology of the user's own social network to promote diversification. Our approach highlights how accounting for and exploiting user's social network in the recommender system design is crucial to mediate filter bubble effects while balancing content diversity with personalization. Provably, opinion clusterization is positively correlated with the influence of recommended content on user opinions. Ultimately, the proposed approach shows the power of socially-aware recommender systems in combating opinion polarization and clusterization phenomena.
