What Could a Body Tell a Social Robot that It Does Not Know?

Humans are extremely efficient in interacting with each other. They not only follow goals to exchange information, but modulate the interaction based on nonverbal cues, knowledge about situational context, and person information in real time. What comes so easy to humans poses a formidable challenge for artificial systems, such as social robots. Providing such systems with sophisticated sensor data that includes expressive behavior and physiological changes of their interaction partner holds much promise, but there is also reason to be skeptical. We will discuss issues of specificity and stability of responses with view to different levels of context.