Abstract
Service robots are expected to become increasingly common. As their capabilities become more advanced, it is also expected that they would be involved in tasks for which a human user would want to know why they do what they are doing. One way to accomplish this is to program robots so that they verbalize (i.e., they are thinking aloud) while they are providing service. This ability is likely to be particularly useful for tasks that involve behavioral norms. The present study used an experimental design to manipulate the level of a robot's ability to verbalize motivations for its behavior (low vs. high) while it was asked by a human to carry out a task with moral implications. The results show that robot verbalizing contributed positively to satisfaction with the robot's performance, and that this impact was mediated by understandability, perceived morality and intellectual stimulation.