@inproceedings { prada05, abstract = {In recent years, virtual environments have evolved from single user and single agent, to multi-user and multi-agent, all interacting, collaborating or competing with each other. This scenario created new challenges for the users’ interaction with the environment, in particular for their interaction with the autonomous synthetic agents. To engage in successful and believable interactions the synthetic agents they must be able to show a coherent set of behaviours responsive to the user’s actions. For example, in scenarios where users and synthetic agents interact as a group it is very important that the interactions follow a believable group dynamics. Focusing on this problem, we have developed a model that supports the dynamics of a group of synthetic agents, inspired by theories of group dynamics developed in human social psychological sciences, driven by a characterization of the different types of interactions that may occur in the group. We have implemented this model into the behaviour of autonomous synthetic characters that collaborate with the user in the resolution of collaborative tasks within a virtual environment. It was used in an experiment that showed that the model had a positive effect on the users’ trust and identification with the synthetic group.}, address = {Utrecht, The Netherlands}, booktitle = {AAMAS'05 - 4th International Joint Conference on Autonomous Agents and Multi Agent Systems}, keywords = {autonomous synthetic characters, group dynamics, collaboration, human-computer interaction, multi-agent systems, virtual environments}, month = {July}, pages = {37-43}, publisher = {ACM}, title = {Believable groups of synthetic characters}, year = {2005}, author = {Rui Prada and Ana Paiva} }