This cross-cultural study$(\mathrm{N}=108)$examines how cultural differences between Japan and Sweden influence participants social behaviors and perceptions when joining a free-standing group of two agents. Agents within the group, embodied as humans, robots, and virtual characters, respectively, use three distinct behaviors, varying with respect to politeness strategy, to request the participant to join on a specific side and position in the group. The experimental results showed that Japanese participants, from a culture characterized by higher power distance, masculinity, uncertainty avoidance, long-term orientation, restraint, and collectivism, were more likely to comply with the agent's request regarding the joining position, compared to Swedish participants. This trend was even more pronounced when comparing different types of embodiment: Japanese participants more strictly complied with human agents than with non-human agents. Additionally, Japanese females and Swedish males adhered more to social norms by avoiding walking between group members (i.e. through the group's o-space) when joining. Second, cultural differences also significantly impacted the perception of agents' politeness behaviors, while the effect of embodiment on feelings of friendliness and closeness varied depending on the culture. We reflect on our results as a basis for highlighting key challenges involved in the design of culturally adapted agents and their behaviors toward enhancing the localization of human-agent interaction.

Politeness and embodiment are pivotal elements in human-agent interactions. While many previous works advocate the positive role of embodiment in enhancing these interactions, it remains unclear how embodiment and politeness affect individuals joining groups. In this paper, we explore how politeness behaviors (verbal and nonverbal) exhibited by three distinct embodiments (humans, robots, and virtual characters) influence individuals’ decisions to join a group of two agents in a controlled experiment (N=54). We assessed agent effectiveness regarding persuasiveness, perceived politeness, and participants’ trajectories when joining the group. We found that embodiment does not significantly impact agent persuasiveness and perceived politeness, but politeness does. Direct and explicit politeness strategies have a higher success rate in persuading participants to join the group at the furthest side. Lastly, participants adhered to social norms when joining at the furthest side, maintained a greater physical distance from humans, chose longer paths, and walked faster when interacting with humans.

Politeness is at the core of the common set of behavioral norms that regulate human communication and is therefore of significant interest in the design of Human-Robot Interactions. In this paper, we investigate how the politeness behaviors of a humanoid robot impact human decisions about where to join a group of two robots. We also evaluate the resulting impact on the perception of the robot's politeness. In a study involving 59 participants, the main (Pepper) robot in the group invited participants to join using six politeness behaviors derived from Brown and Levinson's politeness theory. It requests participants to join the group at the furthest side of the group which involves more effort to reach than a closer side that is also available to the participant but would ignore the request of the robot. We evaluated the robot's effectiveness in terms of persuasiveness, politeness, and clarity. We found that more direct and explicit politeness strategies derived from the theory have a higher level of success in persuading participants to join at the furthest side of the group. We also evaluated participants' adherence to social norms i.e. not walking through the center, or o-space, of the group when joining it. Our results showed that participants tended to adhere to social norms when joining at the furthest side by not walking through the center of the group of robots, even though they were informed that the robots were fully automated.

Multimodal communication is essential in human interactions, as it allows for a more comprehensive and nuanced exchange of information and emotions. The use of multiple communication channels such as speech, body language, and gaze can enhance the clarity and richness of the communication, leading to better understanding and more effective social interactions. This paper investigates the importance of multimodal expressive communication, specifically voice, arm gestures, and gaze, in regulating human-agent interaction when joining a group of two virtual agents in a virtual reality environment. One of the virtual agents in the group uses politeness behaviors based on Brown and Levinson's politeness theory to invite participants to join the group at the side further to them, even though a closer side is available. The study finds that a combination of all modalities (verbal, gaze, arm gesture) is more effective in persuading participants to join the group at the farthest side, and arm gestures alone are more effective than gaze behavior although they are perceived to be less polite. Furthermore, although verbal-only communication can be as persuasive as other modalities, it can place a greater cognitive load on participants. This increased cognitive load may lead to delayed responses in comparison to other modalities. The findings give insight to designers of human-agent interaction systems about the use of multiple communication channels, particularly nonverbal behaviors such as arm gestures, to enhance the effectiveness of persuasive communication but they also need to balance this with other factors such as the impression and perceived politeness of virtual agents.

We present the design and evaluation of a storytelling activity between children and an autonomous robot aiming at nurturing children’s creativity. We assessed whether a robot displaying creative behavior will positively impact children’s creativity skills in a storytelling context. We developed two models for the robot to engage in the storytelling activity: creative model, where the robot generates creative story ideas, and the non-creative model, where the robot generates non-creative story ideas. We also investigated whether the type of the storytelling interaction will have an impact on children’s creativity skills. We used two types of interaction: 1) Collaborative, where the child and the robot collaborate together by taking turns to tell a story. 2) Non-collaborative: where the robot first tells a story to the child and then asks the child to tell it another story. We conducted a between-subjects study with 103 children in four different conditions: Creative collaborative, Non-creative collaborative, Creative non-collaborative and Non-Creative non-collaborative. The children’s stories were evaluated according to the four standard creativity variables: fluency, flexibility, elaboration and originality. Results emphasized that children who interacted with a creative robot showed higher creativity during the interaction than children who interacted with a non-creative robot. Nevertheless, no significant effect of the type of the interaction was found on children’s creativity skills. Our findings are significant to the Child-Robot interaction (cHRI) community since they enrich the scientific understanding of the development of child-robot encounters for educational applications.

When modeling life-like Embodied Conversational Agents (ECAs), conveying politeness through verbal and nonverbal behaviors with persuasive intents is a significant challenge, as it underlies the conventional set of behavioral rules that govern human communication. In the present study, we explore the adherence to such rules in the context of joining a small, freestanding conversational group of agents in VR. In particular, we focus on the behavior adopted by participants while walking towards the agents, and on whether ECAs were treated in the same way human agents normally are. 45 test subjects were invited by an ECA to walk towards the group by applying one of six possible politeness strategies; after freely joining the group, they were asked to rate the agent's politeness according to four distinct aspects (Clarity, Face loss, Positive face, and Negative face). Across all strategies, in 48% of the trials participants were successfully persuaded to join the group at an inconvenient location. Out of those trials, participants adhered to social conventions by not crossing the convex empty space between the group members (o-space) in 75% of them on average. Additionally, analysis of verbal and nonverbal behaviors in ECAs shows that direct request strategies are more effective than indirect ones, although in some cases they may be perceived as less polite.

Politeness behaviors could affect individuals' decisions heavily in their daily lives and may therefore also play an important role in human-agent interactions. This study considers the impact of politeness behaviors made by a virtual agent, already in a small face-to-face conversational group with another agent, on a human participant as they approach to join it in a virtual environment displayed on a monitor. The agent uses five verbal and nonverbal politeness strategies, ranging from indirect and implicit to direct and explicit, in an attempt to influence the participant to join the group at an inconvenient location, which requires more time and effort than a direct route that would ignore the invitation of the agent. In addition to assessing the success of the strategies at influencing participant behavior, the participants' perception of the agent's persuasive behavior is assessed in relation to clarity, face loss, positive face, and negative face. Based on results from a within-subjects experiment with 30 participants, we found that more direct and explicit politeness strategies have a higher level of success when requesting a participant to join a small group at an inconvenient location, but sometimes negatively impact their perception of the agent. A positive politeness strategy was found to be the most effective for both persuasive success and maintaining a positive impression of the agent.

Intelligent Virtual Agents are suitable means for interactive storytelling for children. The engagement level of child interaction with virtual agents is a challenging issue in this area. However, the characteristics of child-agent interaction received moderate to little attention in scientific studies whereas such knowledge may be crucial to design specific applications.