A Review of the Development of Embodied Presentation Agents and Their Application Fields
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paper_title: Coping with Temporal Constraints in Multimedia Presentation Planning

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Computer-based presentation systems enable the realization of effective and dynamic presentation styles that incorporate multiple media. Obvious examples are animated user interface agents which verbally comment on multimedia objects displayed on the screen while performing cross-media and cross-window pointing gestures. The design of such presentations must account for the temporal coordination of media output and the agent's behavior. In this paper we describe a new presentation system which not only creates the multimedia objects to be presented, but also generates a script for presenting the material to the user. In our system, this script is forwarded to an animated presentation agent running the presentation. The paper details the kernel of the system which is a component for planning temporally coordinated multimedia.
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paper_title: A Virtual Human Presenter

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A virtual human presenter is created based on extensions to the JackTM animated agent system. Inputs to the presenter system are in the form of speech texts with embedded commands. most of which relate to the virtual presenter's body language. The system then makes him act as a presenter with presentation skills in realtime 3D animation synchronized with speech outputs. Comments Postprint version. Published in Proceedings of IJCAI-97 Workshop on Animated Interface Agents, August 1997, pages 45-51. This conference paper is available at ScholarlyCommons: http://repository.upenn.edu/hms/17 A Virtual Human Presenter
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paper_title: Character design for soccer commmentary

paper_content:

In this paper we present early work on an animated talking head commentary system called Byrne. The goal of this project is to develop a system which can take the output from the RoboCup soccer simulator, and generate appropriate affective speech and facial expressions, based on the character's personality, emotional state, and the state of play. Here we describe a system which takes pre-analysed simulator output as input, and which generates text marked-up for use by a speech generator and a face animation system. We make heavy use of inter-system standards, so that future versions of Byrne will be able to take advantage of advances in the technologies that it incorporates.
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paper_title: Adding animated presentation agents to the interface

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A growing number of research projects both in academia and industries have started to investigate the use of animated agents in the interface. Such agents, either based on real video, cartoon-style drawings or even model-based 3D graphics, are likely to become integral parts of future user interfaces. To be useful, however, interface agents have to be intelligent in the sense that they exhibit a reasonable behavior. In this paper, we present a system that uses a lifelike character, the so-called PPP Persona, to present multimedia material to the user. This material has been either automatically generated or fetched from the web and modified if necessary. The underlying approach is based on our previous work on multimedia presentation planning. This core approach is complemented by additional concepts, namely the temporal coordination of presentation acts and the consideration of the human-factors dimension of the added visual metaphor.
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paper_title: Employing AI Methods to Control the Behavior of Animated Interface Agents

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Life - like characters are increasingly gaining the attention of researchers and commercial developers of user interfaces . A strong argument in favor of using such characters in the interface is the rich repertoire of options they offer , enabling the emulation of communication styles common in human - human dialog . This contribution presents a framework for the development of presentation agents , which can be used for a broad range of applications including personalized information delivery fromthe WWW .
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paper_title: Employing AI Methods to Control the Behavior of Animated Interface Agents

paper_content:

Life - like characters are increasingly gaining the attention of researchers and commercial developers of user interfaces . A strong argument in favor of using such characters in the interface is the rich repertoire of options they offer , enabling the emulation of communication styles common in human - human dialog . This contribution presents a framework for the development of presentation agents , which can be used for a broad range of applications including personalized information delivery fromthe WWW .
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paper_title: Enhancing Embodied Intelligent Agents with Affective User Modelling

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The objective of this research is the exploration how affective knowledge used in global controlling mechanisms for public information systems with lifelike presentation agents will increase the effectiveness of such systems in terms of information presentation, but also help the user to better explain his/her needs by adopting a more natural conversational style through interactive dialogue.
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paper_title: Recent Developments In Facial Animation: An Inside View

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We report on our recent facial animation work to improve the realism and accuracy of visual speech synthesis. The general approach is to use both staticand dynamic observations of natural speech to ...
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paper_title: Embodied contextual agent in information delivering application

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We aim at building a new human-computer interface for Information Delivering applications: the conversational agent that we have developed is a multimodal believable agent able to converse with the User by exhibiting a synchronized and coherent verbal and nonverbal behavior. The agent is provided with a personality and a social role, that allows her to show her emotion or to refrain from showing it, depending on the context in which the conversation takes place. The agent is provided with a face and a mind. The mind is designed according to a BDI structure that depends on the agent's personality; it evolves dynamically during the conversation, according to the User's dialog moves and to emotions triggered as a consequence of the Interlocutor's move; such cognitive features are then translated into facial behaviors. In this paper, we describe the overall architecture of our system and its various components; in particular, we present our dynamic model of emotions. We illustrate our results with an example of dialog all along the paper. We pay particular attention to the generation of verbal and nonverbal behaviors and to the way they are synchronized and combined with each other. We also discuss how these acts are translated into facial expressions.
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paper_title: Collagen -- Applying Collaborative Discourse Theory to Human-Computer Interaction

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We describe an approach to intelligent user interfaces, based on the idea of making the computer a collaborator, and an application-independent technology for implementing such interfaces.
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paper_title: Social role awareness in animated agents

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This paper promotes {\itshape social role awareness\/} as a desirable capability of animated agents, that are by now strong affective reasoners, but otherwise often lack the social competence observed with humans. In particular, humans may easily adjust their behavior depending on their respective role in a socio-organizational setting, whereas their synthetic pendants tend to be driven mostly by attitudes, emotions, and personality. Our main contribution is the incorporation of `social filter programs' to mental models of animated agents. Those programs may qualify an agent's expression of its emotional state by the social context, thereby enhancing the agent's believability as a conversational partner or virtual teammate. Our implemented system is entirely web-based and demonstrates socially aware animated agents in an environment similar to Hayes-Roth's Cybercaf\'{e}.
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paper_title: The Automated Design of Believable Dialogues for Animated Presentation Teams

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During the last few years, an increasing number of attempts have been made to develop systems that are able to generate presentations automatically. The aim to generate presentation variants on the fly to accommodate for different purposes and user needs is a driving force behind these developments. The availability of multiple media offers the choice between media as well as the possibility to compose media combinations that convey information in a more intelligible and appealing way. The output of such presentation systems comprises mere replications of illustrated texts laid out on a computer screen, but also multimedia documents with timed media, such as video and audio clips, and hypertext-style documents. Trying to deploy the repertoire of skills of human presenters, some R&D projects have begun to use animated characters (or agents) in presentation tasks. Based on either cartoon drawings, recorded video images of persons, or 3-D body models, presentation agents enrich the repertoire of available presentation styles. For instance, consider the presentation of research results at a conference. Even though a slide show, a video clip or a poster may contain all the relevant information, the presence of a skilled speaker in addition to well prepared presentation material is usually much more appealing. A potential strength of animated characters is their ability to convey nonverbal conversational signals that are difficult to communicate in traditional media. In this paper, we investigate a new style for presenting information. We introduce the notion of presentation teams which—rather than addressing the user directly—convey information in the style of performances to be observed by the user. The paper is organized as follows. First, we report on our experience with two single animated presentation agents and explain how to evaluate their success. After that, we move to presentation teams and discuss their potential benefits for presentation tasks. In section 2, we describe the basic steps of our approach to the automated generation of performances with multiple characters. This approach has been applied to two different
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paper_title: Generating Multimedia Presentations for RoboCup Soccer Games

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The automated generation of multimedia reports for time-varying scenes on the basis of visual data constitutes a challenging research goal with a high potential for many interesting applications. In this paper, we report on our work towards an automatic commentator system for RoboCup, the Robot World-Cup Soccer. Rocco (RoboCup-Commentator) is a prototype system that has emerged from our previous work on high-level scene analysis and intelligent multimedia generation. Based on a general conception for multimedia reporting systems, we describe the initial Rocco version which is intended to generate TV-style live reports for matches of the simulator league.
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paper_title: Three robocup simulation league commentator systems

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� Three systems that generate real-time natural language commentary on the RoboCup simulation league are presented, and their similarities, differences, and directions for the future discussed. Although they emphasize different aspects of the commentary problem, all three systems take simulator data as input and generate appropriate, expressive, spoken commentary in real time.
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paper_title: Improvising Linguistic Style: Social and Affective Bases for Agent Personality

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This paper introduces Linguistic Style Improvisation, a theory and set of algorithms for improvisation of spoken utterances by articial agents, with applications to interactive story and dialogue systems. We argue that linguistic style is a key aspect of character, and show how speech act representations common in AI can provide abstract representations from which computer characters can improvise. We show that the mechanisms proposed introduce the possibility of socially oriented agents, meet the requirements that lifelike characters be believable, and satisfy particular criteria for improvisation proposed by Hayes-Roth.
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paper_title: Animated conversation: rule-based generation of facial expression, gesture & spoken intonation for multiple conversational agents

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We describe an implemented system which automatically generates and animates conversations between multiple human-like agents with appropriate and synchronized speech, intonation, facial expressions, and hand gestures. Conversation is created by a dialogue planner that produces the text as well as the intonation of the utterances. The speaker/listener relationship, the text, and the intonation in turn drive facial expressions, lip motions, eye gaze, head motion, and arm gestures generators. Coordinated arm, wrist, and hand motions are invoked to create semantically meaningful gestures. Throughout we will use examples from an actual synthesized, fully animated conversation.
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paper_title: Evaluating users’ experience of a character-enhanced information space

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We created the characters Agneta & Frida with the intent to strengthen and encourage exploration of information spaces. In a followdup study we tried to capture whether users found the characters believable, whether they raised affective responses in users, and whether they created a richer, more narratively oriented, experience of the space. In order to do so, we had to develop new criteria and methods of understanding users' conceptions and affective responses. We discuss the study in detail, as well as the general implications for how to perform user studies and design of characterdenhanced systems.
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paper_title: MPML: A Multimodal Presentation Markup Language with Character Agent Control Functions

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As a new style of effective information presentations and a new multimodal information content production on the World Wide Web (WWW), multimodal presentation using interactive life-like agents with verbal conversation capability appears to be very attractive and important. For this purpose, we have developed Multimodal Presentation Markup Language (MPML), which allows many users to write attractive multimodal presentations easily. MPML is a markup language conformed to Extensible Markup Language (XML). It supports functions for controlling verbal presentation and agent behavior. In this paper, we present the specification, related tools, and application of MPML when used as a tool for composing multimodal presentations on the WWW.
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paper_title: Helper agent: designing an assistant for human-human interaction in a virtual meeting space

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This paper introduces a new application area for agents in the computer interface: the support of human-human interaction. We discuss an interface agent prototype that is designed to support human-human communication in virtual environments. The prototype interacts with users strategically during conversation, spending most of its time listening. The prototype mimics a party host, trying to find a safe common topic for guests whose conversation has lagged. We performed an experimental evaluation of the prototype's ability to assist in cross-cultural conversations. We designed the prototype to introduce safe or unsafe topics to conversation pairs, through a series of questions and suggestions. The agent made positive contributions to participants' experience of the conversation, influenced their perception of each other and of each others' national group, and even seemed to effect their style of behavior. We discuss the implications of our research for the design of social agents to support human-human interaction.
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paper_title: The social life of small graphical chat spaces

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This paper provides a unique quantitative analysis of the social dynamics of three chat rooms in the Microsoft V-Chat graphical chat system. Survey and behavioral data were used to study user experience and activity. 150 V-Chat participants completed a web-based survey, and data logs were collected from three V-Chat rooms over the course of 119 days. This data illustrates the usage patterns of graphical chat systems, and highlights the ways physical proxemics are translated into social interactions in online environments. V-Chat participants actively used gestures, avatars, and movement as part of their social interactions. Analyses of clustering patterns and movement data show that avatars were used to provide nonverbal cues similar to those found in face-to-face interactions. However, use of some graphical features, in particular gestures, declined as users became more experienced with the system. These findings have implications for the design and study of online interactive environments.
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paper_title: Automatic animation of discussions in USENET

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This paper proposes a technique for generating more comprehensible animations from discussions, which are often hard to follow, in USENET. This technique consists of two steps. In the first step, our prototype system generates a scenario from articles in a news thread using the quote relationship. In the second step, it generates an animation based on the scenario, casting 3D avatars as the authors of the articles. We also implemented a prototype system based on this technique and made several animations from articles posted to USENET.
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paper_title: BodyChat: autonomous communicative behaviors in avatars

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Although avatars may resemble animated communicating interface agents, they have for the most part not profited from recent research into autonomous systems. In particular, even though avatars function within conversational environments (for example, chat or games), and even though they often resemble humans (with a head, hands, and a body) they are incapable of representing the kinds of knowledge that humans have about how to use the body during communication. Their appearance does not translate into increased communicative bandwidth. Face-to-face conversation among humans, however, does make extensive use of the visual channel for interaction management where many subtle and even involuntary cues are read from stance, gaze and gesture. We argue that the modeling and animation of such fundamental behavior is crucial for the credibility and effectiveness of the virtual interaction in chat. By treating the avatar as a communicative agent, we propose a method to automate the animation of important communicative behavior, deriving from work in context analysis and discourse theory. BodyChat is a system that allows users to communicate via text while their avatars automatically animate attention, salutations, turn taking, back-channel feedback and facial expression, as well as simple body functions such as the blinking of the eyes. 1. BEHAVIORS IN AVATARS One type of embodied agent that has received much airplay but little serious research attention in the agent community, is the avatar in a graphical chat. An avatar represents a user in a distributed virtual environment, but has until now not been autonomous. That is, it has not had knowledge to act in the absence of explicit control on the part of the user. In most current graphical chat systems the user is obliged to switch between controlling the avatar behavior and typing messages to other users. While the user is creating the message for her interlocutor, her avatar stands motionless or repeats a selected animation sequence. This fails to reflect the natural relationship between the body and the conversation that is taking place, potentially giving misleading or even conflicting visual
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paper_title: A flexible platform for building applications with life-like characters

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During the last years, an increasing number of R&D projects has started to deploy life-like characters for presentation tasks in a diverse range of application areas, including, for example, E-Commerce, E-learning, and help systems. Depending on factors, such as the degree of interactivity and the number of the deployed characters, different architectures have been proposed for system implementation. In this contribution, we first analyse a number of existing user interfaces with presentation characters from an architectural point of view. We then introduce the MIAU platform and illustrate by means of illustrated generation examples how MIAU can be used for the realization of character applications with different conversational settings. Finally, we sketch a number of potential application fields for the MIAU platform
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paper_title: Improv: a system for scripting interactive actors in virtual worlds

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Improv is a system for the creation of real−time behavior−based animated actors. There have been several recent efforts to build network distributed autonomous agents. But in general these efforts do not focus on the author’s view. To create rich interactive worlds inhabited by believable animated actors, authors need the proper tools. Improv provides tools to create actors that respond to users and to each other in real−time, with personalities and moods consistent with the author’s goals and intentions. Improv consists of two subsystems. The first subsystem is an Animation Engine that uses procedural techniques to enable authors to create layered, continuous, non−repetitive motions and smooth transitions between them. The second subsystem is a Behavior Engine that enables authors to create sophisticated rules governing how actors communicate, change, and make decisions. The combined system provides an integrated set of tools for authoring the "minds" and "bodies" of interactive actors. The system uses an english−style scripting language so that creative experts who are not primarily programmers can create powerful interactive applications.
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paper_title: Guiding interactive drama

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In traditional drama, an audience watches a story presented by characters on a stage. Interactive Drama changes the audience to a single User who enters that stage, interacting with the characters, and participating in the story. Computer-based interactive drama allows a User to interact with simulated worlds which are inhabited by dynamic and complex autonomous characters and shaped by a flexible, aesthetically pleasing story. Unlike the actions of characters in a play, the actions of the User are not controlled by the artist. The problem is to shape the User's experience to conform to the set of themes and ideas to be conveyed. This work proposes this problem can be solved by dynamically monitoring and subtly guiding the experience of the User. ::: This dissertation describes an architecture called Moe that is designed to provide dramatic guidance. Moe uses abstract, adversary search with an aesthetic evaluation function to decide how and when to guide the User's experience. The first technical achievement of this work is a demonstration of the ability to capture a dramatic aesthetic (for one interactive drama) in an automated evaluation function that can examine an experience and determine its quality, much as a movie critic determines the quality of a film. This result is supported by statistically demonstrating a high degree of correlation (r =.87) between the evaluation function and the human artist. ::: The second main technical achievement of this work is the implementation of three such strategies (SAS and SAS+, both based on random sampling; and MMFC, which uses memoization to implement a full-depth search) and a search state that seem capable of effectively modelling and guiding an interactive dramatic experience. Moe has not yet been connected to a running interactive experience, but instead Moe has been tested with a variety of Simulated User Types. On "average" Users, SAS, SAS+, and MMFC are able to improve Users' experiences from the 50th percentile, to the 94th, 98th, and 99th percentile, respectively. This is a large and artistically meaningful increase. ::: This dissertation describes the first implementation of a system designed to provide centralized dramatic guidance in an interactive drama.
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paper_title: Dynamic Generation, Management and Resolution of Interactive Plots

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Abstract Rapid advances in entertainment technology necessitate the development of computational models for interactive plots capable of creating engaging stories that are meaningfully interactive. This work describes a computational framework for supporting dynamic generation, management and resolution of interactive plots. In this framework, the user takes the place of the story protagonist. The rest of the cast consists of discrete computer characters, each playing specific roles in the story. The plot is dynamically shaped by the interaction between the user and the rest of the cast. This framework supports an Aristotelian plot conception, in which a conflict between antagonistic forces develops out of an initial situation. The plot moves from this initial situation towards its antagonistic climax, through a sequence of conflicts, and then towards an unambiguous solution at the end. This paper describes dynamic techniques that analyze the evolving plot to support user participation, adopt dramatically interesting story developments and resolve the plot in engaging ways based on the motives of the characters involved. This framework has been implemented as part of DEFACTO, a research project for designing interactive story systems.
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paper_title: Embodied agents for multi-party dialogue in immersive virtual worlds

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Immersive virtual worlds are increasingly being used for education, training, and entertainment, and virtual humans that can interact with human users in these worlds play many important roles. However, current computational models of dialogue do not address the issues that arise with face-to-face communication situated in three-dimensional worlds, such as the proximity and attentional focus of others, the ability to maintain multi-party conversations, and the interplay between speech and nonverbal signals. This paper presents a new model that integrates and extends prior work on spoken dialogue and embodied conversational agents, and describes an initial implementation that has been applied to training in virtual reality.
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paper_title: The Cooperative Contract in Interactive Entertainment

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Interactions with computer games demonstrate many of the same social and communicative c onventions that are seen in conversations between people. I propose that a co-operative contract exists between computer game players and game systems (or their designers) that licenses both the game players’ and the game designers’ understanding of what components of the game mean.
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paper_title: Interactive pedagogical drama

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This paper describes an agent-based approach to realizing interactive pedagogical drama. Characters choose their actions autonomously, while director and cinematographer agents manage the action and its presentation in order to maintain story structure, achieve pedagogical goals, and present the dynamic story to as to achieve the best dramatic effect. Artistic standards must be maintained while permitting substantial variability in story scenario. To achieve these objectives, scripted dialog is deconstructed into elements that are portrayed by agents with emotion models. Learners influence how the drama unfolds by controlling the intentions of one or more characters, who then behave in accordance with those intentions. Interactions between characters create opportunities to move the story in pedagogically useful directions, which the automated director exploits. This approach is realized in the multimedia title Carmen’s Bright IDEAS, an interactive health intervention designed to improve the problem solving skills of mothers of pediatric cancer patients.
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paper_title: A Dramatised Actant Model for Interactive Improvisational Plays

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We want to provide children, who have been shown to be highly skilled improvisers, with synthetic actors for interactive improvisational plays. Using a conflict oriented play structure we let them experience dramatic situations. Our Dramatised Actant Model maintains a dynamic balance between the opposing forces: a user-controlled avatar and several system characters. The model ensures there is a reasonable amount of interaction between the virtual characters even if the user is not actively contributing to the emergent narrative. We illustrate how the model can be instantiated and realised by presenting a first scenario called "The Black Sheep". We also give an overview of our 3D virtual environment platform and deliberative agent architecture that we have used to implement the virtual puppet theatre.
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paper_title: Computers as Theatre

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From the Publisher: ::: features a new chapter that takes the reader through virtual reality and beyond to a new level of human computer interaction that is genuinely transforming. Like its predecessor, this book presents a new theory of human-computer activity.
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paper_title: Towards Integrating Plot and Character for Interactive Drama

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The authors are currently engaged in a three year collaboration to build an interactive story world integrating believable agents and interactive plot. This paper provides a brief description of the project goals and design requirements, discusses the problem of autonomy in the context of story-based believable agents, and describes an architecture that uses the dramatic beat as a s tructural principle to integrate plot and character.
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paper_title: Interacting with virtual characters in interactive storytelling

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In recent years, several paradigms have emerged for interactive storytelling. In character-based storytelling, plot generation is based on the behaviour of autonomous characters. In this paper, we describe user interaction in a fully-implemented prototype of an interactive storytelling system. We describe the planning techniques used to control autonomous characters, which derive from HTN planning. The hierarchical task network representing a characters' potential behaviour constitute a target for user intervention, both in terms of narrative goals and in terms of physical actions carried out on stage. We introduce two different mechanisms for user interaction: direct physical interaction with virtual objects and interaction with synthetic characters through speech understanding. Physical intervention exists for the user in on-stage interaction through an invisible avatar: this enables him to remove or displace objects of narrative significance that are resources for character's actions, thus causing these actions to fail. Through linguistic intervention, the user can influence the autonomous characters in various ways, by providing them with information that will solve some of their narrative goals, instructing them to take direct action, or giving advice on the most appropriate behaviour. We illustrate these functionalities with examples of system-generated behaviour and conclude with a discussion of scalability issues.
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paper_title: An Oz-Centric Review of Interactive Drama and Believable Agents

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Believable agents are autonomous agents that exhibit rich personalities. Interactive dramas take place in virtual worlds inhabited by believable agents with whom an audience interacts. In the course of this interaction, the audience experiences a story. This paper presents the research philosophy behind the Oz Project, a research group at CMU that has spent the last ten years studying believable agents and interactive drama. The paper then surveys current work from an Oz perspective.
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paper_title: Toward the holodeck: integrating graphics, sound, character and story

paper_content:

We describe an initial prototype of a holodeck- like environment that we have created for the Mission Rehearsal Exercise Project. The goal of the project is to create an experience learning system where the participants are immersed in an environment where they can encounter the sights, sounds, and circumstances of real-world scenarios. Virtual humans act as characters and coaches in an interactive story with pedagogical goals.
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paper_title: Computers as Theatre

paper_content:

From the Publisher: ::: features a new chapter that takes the reader through virtual reality and beyond to a new level of human computer interaction that is genuinely transforming. Like its predecessor, this book presents a new theory of human-computer activity.
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paper_title: ANVIL - A Generic Annotation Tool for Multimodal Dialogue

paper_content:

Anvil is a tool for the annotation of audiovisual material containing multimodal dialogue. Annotation takes place on freely definable, multiple layers (tracks) by inserting time-anchored elements that hold a number of typed attribute-value pairs. Higher-level elements (suprasegmental) consist of a sequence of elements. Attributes contain symbols or cross-level links to arbitrary other elements. Anvil is highly generic (usable with different annotation schemes), platform-independent, XMLbased and fitted with an intuitive graphical user interface. For project integration, Anvil offers the import of speech transcription and export of text and table data for further statistical processing.
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paper_title: The ALIVE system: wireless, full-body interaction with autonomous agents

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The cumbersome nature of wired interfaces often limits the range of application of virtual environments. In this paper, we discuss the design and implementation of a novel system, called ALIVE, which allows unencumbered full-body interaction between a human participant and a rich graphical world inhabited by autonomous agents. Based on results obtained with thousands of users, the paper argues that this kind of system can provide more complex and very different experiences than traditional virtual reality systems. The ALIVE system significantly broadens the range of potential applications of virtual reality systems: in particular, the paper discusses novel applications in the area of training and teaching, entertainment, and digital assistants or interface agents. We give an overview of the methods used in the implementation of the existing ALIVE systems.
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Title: A Review of the Development of Embodied Presentation Agents and Their Application Fields

Section 1: Introduction
Description 1: This section introduces the concept of embodied presentation agents, their evolution over the last decade in HCI, and the scope of their application.

Section 2: From TV-style Presenters to Interactive Performances
Description 2: This section discusses the different types of presentation settings from non-interactive TV-style presenting to fully interactive performances involving user engagement.

Section 3: Non-interactive Presenters
Description 3: This section reviews various non-interactive virtual presenters developed over the years, focusing on their manual and automated scripting processes.

Section 4: PPP Persona
Description 4: This section delves into the design and functionality of the PPP-Persona, a personalized presentation agent, and its plan-based approach for generating presentation scripts.

Section 5: Conversational Characters
Description 5: This section examines systems aiming to emulate face-to-face interactions between users and virtual characters, distinguishing between characters with restricted input understanding and those engaging in multimodal conversations.

Section 6: Presentation Teams
Description 6: This section explores the use of multiple presentation agents working together in role-play scenarios to convey information more effectively.

Section 7: Reporter Teams
Description 7: This section presents examples of systems using multiple characters to provide live commentary on dynamic events, such as the Rocco II system for Robot World-Cup Soccer.

Section 8: Other Approaches with Multiple Characters
Description 8: This section reviews other systems employing multiple characters to simulate conversations, often in training and dispute resolution contexts.

Section 9: Presentation Teams that Represent Human Users
Description 9: This section discusses applications where avatars represent real humans in scenarios like the Magic Monitor and Avatar Arena systems.

Section 10: Interactive Performances
Description 10: This section touches on user participation in performances through systems like the MIAU platform, where users can interact with characters in real-time.

Section 11: Other Work Related to Interactive Performances
Description 11: This section reviews related work in interactive drama and other systems incorporating user interaction to influence story and performance direction.

Section 12: The Interactive CrossTalk Installation
Description 12: This section describes the CrossTalk installation, a mixed approach combining manually scripted and dynamically generated dialogues for public demonstrations.

Section 13: Conclusions
Description 13: This section summarizes the evolution of embodied presentation agents, highlighting the contributions and future research directions towards improving their multimodal communication and learning capabilities.