This study explores how a robotpsilas physical or virtual presence affects unconscious human perception of the robot as a social partner. Subjects collaborated on simple book-moving tasks with either a physically present humanoid robot or a video-displayed robot. Each task examined a single aspect of interaction: greetings, cooperation, trust, and personal space. Subjects readily greeted and cooperated with the robot in both conditions. However, subjects were more likely to fulfill an unusual instruction and to afford greater personal space to the robot in the physical condition than in the video-displayed condition. The same tendencies occurred when the virtual robot was supplemented by disambiguating 3-D information.