Toward a Guide Agent who Actively Intervene Inter-user Conversation - Timing Definition and Trial of Automatic Detection using Low-level Nonverbal Features

As the advance of embodied conversational agent (ECA) technologies, there are more and more real-world deployed applications of ECAâ??s. The guides in museums or exhibitions are typical examples. However, in these situations, the agent systems usually need to engage groups of visitors rather than individual ones. In such a multi-user situation, which is much more complex than single user one, specialized additional features are required. One of them is the ability for the agent to smoothly intervene user-user conversation. In order to realize this, at first, a Wizard-of-Oz (WOZ) experiment was conducted for collecting human interaction data. By analyzing the collected data corpus, four kinds of timings that potentially allow the agent to do intervention were found. The collected corpus was then annotated with these defined timings by recruited evaluators with a dedicated and intuitive tool. Finally, as the trial of the possibility of automatic detection on these timings, the use of non-verbal low level features were able to achieve a moderate accuracy.