Engagement detection based on mutli-party cues for human robot interaction

In this paper, we address the problematic of automatic detection of engagement in multi-party Human-Robot Interaction scenarios. The aim is to investigate to what extent are we able to infer the engagement of one of the entities of a group based solely on the cues of the other entities present in the interaction. In a scenario featuring 3 entities: 2 participants and a robot, we extract behavioural cues that concern each of the entities, we then build models based solely on each of these entities´ cues and on combinations of them to predict the engagement level of each of the participants. Person-level cross validation shows that we are capable of detecting the engagement of the participant in question using solely the behavioural cues of the robot with a high accuracy compared to using the participant´s cues himself (75.91% vs. 74.32%). Moreover using the behavioural cues of the other participant is also informative where it permits the detection of the engagement of the participant in question at an accuracy of 62.15% on average. The correlation between the features of the other participant with the engagement labels of the participant in question suggests a high cohesion between the two participants. In addition, the similarity of the most significantly correlated features among the two participants suggests a high synchrony between the two parties.