Product reviews or user opinions represent a peculiar information source that can be exploited in supporting travel decision making. Product reviews provide other user's experiences and, when consulted during a decision making process, tend to increase the user's confidence in the decision by providing a feeling of greater objectivity in the product description compared with commercial information. Notwithstanding their value, until now, product reviews have not been integrated in travel recommender systems, they have been used only in dedicated web sites. In
Francesco Ricci, René T. A. Wietsma