  This study presents novel strategies to investigate the mutual influence of
trust and group dynamics in children-robot interaction. We implemented a
game-like experimental activity with the humanoid robot iCub and designed a
questionnaire to assess how the children perceived the interaction. We also aim
to verify if the sensors, setups, and tasks are suitable for studying such
aspects. The questionnaires' results demonstrate that youths perceive iCub as a
friend and, typically, in a positive way. Other preliminary results suggest
that, generally, children trusted iCub during the activity and, after its
mistakes, they tried to reassure it with sentences such as: "Don't worry iCub,
we forgive you". Furthermore, trust towards the robot in group cognitive
activity appears to change according to gender: after two consecutive mistakes
by the robot, girls tended to trust iCub more than boys. Finally, no
significant difference has been evidenced between different age groups across
points computed from the game and the self-reported scales. The tool we
proposed is suitable for studying trust in human-robot interaction (HRI) across
different ages and seems appropriate to understand the mechanism of trust in
group interactions.
