A detailed analysis of the impact of tie strength and conflicts on social influence

Group Recommendation Systems (GRS) are personalization systems that provide recommendations to groups of people considering the initial preferences of each group's member, with the aim to maximize the satisfaction of the whole group. Since recent psychological studies evidence that people's satisfaction is influenced by the satisfaction of other people with whom they perform an activity, it is important to consider human aspects and social characteristics that a.ect the changes in individual's satisfactions in the recommendations generation process. In this work, we start an experimental analysis on how ties' strength and possible conflicts in a relationship can influence the individual's satisfactions, with the aim to derive a model that can be used to adapt individual utilities to the "Group Context" before aggregating them into the group's ones. Our hypothesis is that there is a direct correlation between tie strength and positive shi.ing, but the presence of con.ict, instead, can lead to a negative influence, causing a dri.ing further apart between people's satisfactions. Results confirm these hypotheses, but also suggest that these two factors are not enough to define a general model and that other factors must be considered.