How a robot should give advice

With advances in robotics, robots can give advice and help using natural language. The field of HRI, however, has not yet developed a communication strategy for giving advice effectively. Drawing on literature in politeness and informal speech, we propose options for a robot's help-giving speech-using hedges or discourse markers, both of which can mitigate the commanding tone implied in direct statements of advice. To test these options, we experimentally compared two help-giving strategies depicted in videos of human and robot helpers. We found that when robot and human helpers used a hedge or discourse markers, they seemed more considerate and likeable, and less controlling. The robot that used discourse markers had even more impact than the human helper. The findings suggest that communication strategies derived from speech used when people help each other in natural settings can be effective for planning the help dialogues of robotic assistants.