## 3 Experimental Studies and Results
### Experiments 3: The Robot Listens to a Story
A participant sat in a room in front of the two robots, identified by square and triangle marks on their bodies. The first robot said that it is ready to listen to a story. The subject took the cards from the stack and had to organize them into a story. While narrating, the subject was asked to show the robot the card corresponding to the current part of the story. At the end of the story, the robot expressed its gratitude and asked to tell the next story to the other robot. Within the setup of the experiment, three zones of attention were distinguished--a participant can organize the cards on the table and can show the cards to the left or the right robot. This setup ensured higher precision of the user recognition system, which was detecting the face orientation rather than the gaze itself. The subject could communicate with the left and right robots from the same position at the table, so the robots constantly maintained the corresponding gaze behavior. For example, each robot could respond to the user's gaze even if the user told a story to the other robot. Following the experiment, the subject had to express their preference for the triangle robot, the square robot, or both robots equally, as well as evaluate each robot on a five-point scale. While \"listening\", the hands of the robots were controlled by the inactive component, which initiates permanent minor movements. Additionally, during the speech replies, the hands were controlled by more significant gestures that were coordinated to the utterances. At the same time, the head and eyes were constantly controlled by the two scripts responsible for the social gaze. When a person looked away from the robot (e.g.,  
Figure 5: Example of stimulus material—a graphic story by [PERSON]. Each story was represented as a stack of separate cards in random order. looked aside or looked at the table to follow the cards), each of the robots looked down--at the table with the cards. When a person looked at the robot, the first robot (marked with a square) looked back, raised its head, opened its eyelids, and raised its eyebrows (Table 1), while the second robot (marked with a triangle) demonstrated the side gaze, looking left or right and randomly changing the direction. We used the Emotional Intelligence Test (EmIn) [42; 43] to evaluate the level of emotional intelligence of the participants. The questionnaire is based on the interpretation of emotional intelligence as the ability to understand one's own and others' emotions, as well as to control one's own emotions. This understanding implies that a person (a) recognizes the presence of an emotional experience in oneself or another person, (b) identifies the expression and can find a verbal designation for one's own or another's emotion, and (c) understands the causes and effects of that emotional experience. Controlling emotions means that the person controls the intensity and external expression and can, if necessary, arbitrarily evoke a particular emotion. The test suggests an aggregated score of emotional intelligence, but we expected that the recognition of others' emotions would play a major role in the perception of the robots. We also evaluated the accuracy of the recognition system. The automatically obtained data was compared with the observed gaze of the subjects during the experiment. The subject's gaze on the robot was defined as a movement of the gaze and head in the direction of the robot starting from 1 s. The number of reactions roughly corresponded to the number of gazes. The system was performing with a redundancy of 133% (for 1988 gazes, it demonstrated about 2650 responsive actions), the majority of redundant reactions were demonstrated during long human gazes (more than 30 s), when the system could execute several gaze responses. The statistics of real gazes were obtained by qualitative analysis of video recordings of the experiment. Taking into account the slight redundancy in performance for long gazes, the system was considered appropriate to execute gaze control in the actual communication.