Group Decision-Making and Designing Group Recommender Systems

Designing (group) recommender systems in the travel and tourism domain is a difficult task, considering the complexity and intangibility of a tourism product, i.e., (i) it is a bundle of products and services; (ii) it is an emotional experience; (iii) it is difficult to characterize users’ travel-related preferences explicitly (especially in the early phase of the travel decision-making process); and, finally, (iv) traveling is usually a group activity. Therefore, to support travel-related group decision-making process and to suggest appropriate items introduce new challenges into the overall picture. In comparison to individual decision-making and recommendations, when a group of people is faced with a decision task, group dynamics comes to play. In fact, group members’ preferences are usually not so uniform; thus a conflict might arise. In a group discussion, opinion shift might occur due to group members’ influence on each other by exchanging experiences, information, preferences, etc. Moreover, emotional contagion is a phenomenon that explains how satisfaction/dissatisfaction of one member might contaminate the others in the group. All of these group behavioral aspects are greatly affected by group members’ individual personalities and their intragroup relationships. In this chapter, we provide an overview of the research done in the field of group decision-making, group recommender systems, and group personalization in the travel and tourism domain.