It is known that humans' ambiguous expressions often work effectively to avoid risks latent in interpersonal communication. There have been several attempts to enable agents to use ambiguous expressions as efficiently as humans. However, the ambiguous expressions will not always be appropriate to the circumstances. The agents therefore need to choose the most appropriate expressions that will suit the context. In this paper, to realize agents of this nature, we investigate the relationship between the ambiguities of the agents' facial expressions and their appropriateness to the context. We formulate a hypothesis that the agent's ambiguous facial expression works more effectively when a recipient is in a less positive or less negative context. We verify this hypothesis and show a model of contextual appropriateness of ambiguous facial expressions. In this paper, based on our previous work, we provide more detailed information and discuss it in greater depth to obtain novel insights.
This manuscript proposes a long arrow mouse cursor for making users perceive a sense of self-ownership. A long arrow mouse cursor is a designed mouse cursor represented by a long arrow that starts closely at your body and ends to a target on the computer screen. A sense of self-ownership is a feeling of belonging to one's body and has the potential for making user interface more natural and intuitive. This manuscript evaluates an influence of our basic idea of a long arrow mouse cursor and visibility of the hand on a sense of self-ownership as well as performance of mouse manipulation. This manuscript conducts an experiment with a simple clicking task to evaluate the long arrow mouse cursor. The result shows that a long arrow mouse cursor and visibility of the hand have a significant impact on a sense of self-ownership.