Analysing Recommender Systems Impact on Users' Choices

In this paper we introduce a novel model for simulating the choice making procedure of users under the influence of a Recommender System (RS). Our model leverages the knowledge of users’ preferences and simulates repeated choices. We investigate the evolution of these simulated choices in the presence of different RSs and analyse their impact on the Gini index, as indicator of choice diversity. Running the simulation we have observed that all the considered RSs increase the awareness of the users about the items while they affect the aggregated choice diversity differently.

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