@inproceedings { prada07, abstract = {Autonomous characters in virtual environments have the potential to improve the interaction experience of users, specially, their social experience.This effect is driven by the interactions occurring between users and the autonomous characters, that in certain scenarios can be in the context of a group.However, for these group interactions to be successful, it is not enough to assure that the autonomous characters behave in a coherent manner from an individual perspective,but it is also necessary that they exhibit behaviours that are coherent with the group composition, context and structure. Therefore, we have developed a model to support believable group dynamics of autonomous characters, inspired in theories developed in human social psychological sciences. This model defines the knowledge that each individual should build about the others and about the group it belongs, and how this knowledge drives their interactions in the group. The model was integrated in the mind of the autonomous characters that perform a collaborative task, in a computer game, with a human player. The game was used in a study that showed that players' interaction experience was better when interaction with groups that followed our model, namely, regarding trust and social identification with the group. In addition, we found some evidence that players prefer playing in groups that have higher level of conflict.}, address = {Salzburg, Austria}, booktitle = {ACE'2007 - 4th International Conference on Advances in Computer Entertainment Technology}, keywords = {autonomous characters, group dynamics, human-computer interaction, user studies}, month = {June}, pages = {25-32}, publisher = {ACM }, series = {ACM International Conference Proceeding Series}, title = {The user in the group: evaluating the effects of autonomous group dynamics}, volume = {203}, year = {2007}, author = {Rui Prada and Nuno Otero and Ana Paiva} }