In both physical and virtual environments, small group interactions significantly shape our social experiences. Understanding and replicating situated group interactions with virtual agents or physical robots pose possibilities and challenges. Central to these challenges lies the critical aspect of politeness, which serves as a fundamental cornerstone in shaping our social interactions. This PhD thesis investigates the profound significance of politeness strategies in shaping social interactions within small free-standing conversational groups in physical and virtual environments with humanoid artificial agents. It particularly focuses on their adaptability to virtual characters or Embodied Conversational Agents (ECAs) and Human-Robot Interaction (HRI). The thesis explores the impact of these strategies on persuasiveness, adherence to social norms, and the formation of positive perceptions during interactions between participants and virtual agents or humanoid robots while joining a group of artificial humanoid agents. It involves a series of user studies with an experimental setup, which entails presenting participants with dilemmas in either a virtual or physical environment. Participants should decide between expending more effort to comply with the agent’s request or opting for a least-effort alternative to join a group while ignoring the request. Additionally, the setup evaluates participant responses to various politeness strategies expressed by virtual agents or robots when extending invitations to join a small, free-standing group. The research contributes by defining behaviors aligned with politeness strategies, revealing participant adherence to social norms even in situations requiring more effortful choices, and pinpointing optimal behaviors based on criteria such as persuasiveness, politeness, and social adherence. Ultimately, the findings provide insights into the indispensable role of politeness strategies in Human-Agent Interaction to gently influence the decisions of humans while maintaining positive relations with them. These insights pave the way for designing more effective and socially acceptable behaviors for virtual agents and robots across diverse domains.

I både fysiska och virtuella miljöer formar små gruppinteraktioner avsevärt våra sociala upplevelser. Att förstå och replikera sammanhangsbaserade gruppinteraktioner med virtuella agenter eller fysiska robotar innebär möjligheter och utmaningar. Centralt för dessa utmaningar är den kritiska aspekten andående artighet, som fungerar som en grundläggande hörnsten i att forma våra sociala interaktioner. Denna doktorsavhandling undersöker den djupa betydelsen av artighetsstrategier för att forma sociala interaktioner inom små fristående samtalsgrupper i fysiska och virtuella miljöer med humanoida artificiella agenter. Den fokuserar särskilt på deras anpassningsförmåga till virtuella karaktärer eller Embodied Conversational Agents (ECA) och Human-Robot Interaction (HRI). Avhandlingen undersöker effekten av dessa strategier på övertalningsförmåga, efterlevnad av sociala normer och bildandet av positiva uppfattningar under interaktioner mellan deltagare och virtuella agenter eller humanoida robotar samtidigt som de ansluter till en grupp artificiella humanoida agenter. Den består av en serie användarstudier med experimentupplägg, vilket innebär att deltagarna ställs inför dilemman i antingen en virtuell eller fysisk miljö. Deltagarna får välja mellan att lägga ner mer ansträngning på att följa agentens begäran eller välja ett minst ansträngningsalternativ för att ansluta till en grupp samtidigt som de ignorerar begäran. Dessutom utvärderar experimentet deltagarnas svar på olika artighetsstrategier som uttrycks av virtuella agenter eller robotar när de inbjuder till att ansluta till en små, fristående grupp. Forskningen bidrar genom att definiera beteenden i linje med artighetsstrategier, avslöja deltagarnas efterlevnad av sociala normer även i situationer som kräver mer ansträngande val, och fastställa optimala beteenden baserat på kriterier som övertalningsförmåga, artighet och social efterlevnad. Slutligen ger resultaten insikter i den oumbärliga rollen av artighetsstrategier i interaktion mellan människa och agent för att varsamt påverka människors beslut samtidigt som de bibehåller positiva relationer med dem. Dessa insikter banar väg för att utforma mer effektiva och socialt acceptabla beteenden för virtuella agenter och robotar över olika domäner.

Politeness is a crucial aspect of human social interactions. While the infuence of politeness is well understood in human groups, it remains underexplored in group interactions with robots. Therefore, in this paper, we conduct an initial exploration into the infuence of the presence of humanoid robots on their persuasiveness and perceived politeness in small groups. We conducted a user study (N = 119) with co-present and remote robots that invited participants to join the group using six politeness behaviors derived from Brown and Levinson’s politeness theory. It requests participants to join them at the furthest side of the group, even though a closer side is also available to them, but would ignore the robot’s request. The results show that co-present robots are perceived to be less persuasive than remote ones. However, co-presence enhances the clarity of the robot’s requests and the perceived freedom of action while decreasing the perceived friendliness and ofensiveness. 

Politeness and embodiment are pivotal elements in Human-Agent Interactions. While many previous works advocate the positive role of embodiment in enhancing Human-Agent Interactions, it remains unclear how embodiment and politeness affect individuals joining groups. In this paper, we explore how polite 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 polite behaviors do. Direct and explicit politeness strategies have a higher success rate in persuading participants to join 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 critical for shaping human-human interactions and therefore seems an important consideration in human interactions with Embodied Conversational Agents (ECAs). However, the impact of artificially-generated politeness behaviors on humans in Virtual Environments (VE) is not clear. We explore the impact of immersiveness on the perceived politeness and consequent persuasive abilities of ECAs in a small group context. A user study with two main conditions, immersive and non-immersive, was conducted with 66 participants. In the immersive condition, participants were fully immersed in virtual reality (HMD, walking freely), while in the non-immersive condition, participants used a desktop computer interface (screen display, mouse and keyboard control). In both conditions, the primary agent in a group of two ECAs invited participants to join the group using six politeness behaviors derived from Brown and Levinson's politeness theory. While the results of the study did not indicate any significant differences between the immersive and non-immersive conditions in terms of persuasiveness and offensiveness, in the immersive condition, participants perceived the ECAs as less friendly and found their requests to be less clear. On the other hand, participants in the immersive condition reported a greater sense of freedom. Furthermore, the non-immersive condition showed higher adherence to social norms compared to the immersive condition. These findings emphasize the significance of examining immersiveness on the persuasiveness of ECAs and their perceived politeness and social adherence by humans in human-agent interactions within small groups.

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.

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 \textit{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. 

Urban spaces are defined by degrees of axial and convex extension. Space Syntax research has predominantly emphasized axial lines and maps and considered convexity through isovists and visibility graphs. Axiality emphasizes movement or flow and creates axial maps as two-dimensional networks. Convexity of urban space is aural and shaped by vision and sound in three dimensions. It is represented by convex maps of stretchable polygons (described furthermore by an adjacency scene graph within the polygons) and remain fuzzy conceptualizations because of their property as three-dimensional objects. Kevin Lynch's morphology of imageability and Michael Southworth’s soundscapes can be used to create diagrammatic representations of convex spaces as townscape representations. This paper explores the convergence of Space Syntax and imageability, soundscape and townscape theories for analysing three dimensional urban spaces in two dimensional representations. The ‘urban envelope’ creates an assemblage of building façade and street sections as fronts and empty spaces as voids surrounding one viewshed. The viewshed like an isovist or visibility graph on map depicts convexity, but with an image collage of fronts and voids (surrounding buildings and streets) distorted on a map. The urban envelope is used as an urban design drawing board in a new software for City Information Modelling (CIM) that is under development. This paper aims to inspire synergetic ways to juxtapose morphological and urban design traditions to discuss applications of morphological theories and urban design practices.

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.

The analysis and simulation of the interactions that occur in group situations is important when humans and artificial agents, physical or virtual, must coordinate when inhabiting similar spaces or even collaborate, as in the case of human-robot teams. Artificial systems should adapt to the natural interfaces of humans rather than the other way around. Such systems should be sensitive to human behaviors, which are often social in nature, and account for human capabilities when planning their own behaviors. A limiting factor relates to our understanding of how humans behave with respect to each other and with artificial embodiments, such as robots. To this end, we present CongreG8 (pronounced 'con-gregate'), a novel dataset containing the full-body motions of free-standing conversational groups of three humans and a newcomer that approaches the groups with the intent of joining them. The aim has been to collect an accurate and detailed set of positioning, orienting and full-body behaviors when a newcomer approaches and joins a small group. The dataset contains trials from human and robot newcomers. Additionally, it includes questionnaires about the personality of participants (BFI-10), their perception of robots (Godspeed), and custom human/robot interaction questions. An overview and analysis of the dataset is also provided, which suggests that human groups are more likely to alter their configuration to accommodate a human newcomer than a robot newcomer. We conclude by providing three use cases that the dataset has already been applied to in the domains of behavior detection and generation in real and virtual environments.