@inproceedings { gama12, abstract = {Conversational agents have been subject of extensive research. An increasingly wider number of such agents simulate affective behavior in order to convey familiarity and increase believability. Nevertheless, the evolution of social relationships among people occurs gradually and the degree of intimacy associated with such relationships regulates people’s behaviors. Similarly, we must take into account the progressive growth of relationships when modeling user-agent interaction. In this paper we present a model that regulates the development of user-agent relationships, articulating the Social Penetration Theory with personality modeling. User tests showed that gradual relationship build- ing achieved through the implementation of our model makes an agent more interesting, while increasing its believability, engagement and fun.}, address = {Eindhoven, The Netherlands}, booktitle = {Intelligent Virtual Agents IVA'2012}, keywords = {Intelligent Virtual Agents}, month = {September}, pages = {319-326}, publisher = {Springer Berlin / Heidelberg}, series = {Lecture Notes in Computer Science}, title = {A Model for Social Regulation of User-Agent Relationships}, volume = {7502/2004}, year = {2012}, author = {Sandra Gama and Gabriel Barata and Daniel Gonçalves and Rui Prada and Ana Paiva} }