virtual agent Papers

Embodied conversational agents (ECAs) are designed to provide natural and intuitive communication with a human user. One major current topic in agent design consequently is to enhance their believability, often by incorporating internal models of emotions or motivations. As psychological theories often lack the necessary details for direct implementation, many agent modelers currently rely on models that are rather marginal in current psychological research, or models that are created ad hoc with little theoretical and... Read more

Rapport, the feeling of being "in sync" with your conversational partners, is argued to underlie many desirable social effects. By generating proper verbal and nonverbal behaviors, virtual humans have been seen to create rapport during interactions with human users. In this paper, we introduce our approach to creating rapport following Tickle-Degnen and Rosenberg’s threefactor (positivity, mutual attention and coordination) theory of rapport. By comparing with a previously published virtual agent, the ... Read more

Location-aware ambient environments are relevant in designing interactive virtual characters. However, they raise several questions about spatial behaviors to be displayed by virtual characters, and about the perception of virtual characters by users. We designed a location-aware virtual agent that adapts its spatial behavior to users' and objects' locations during a search task in a smart room. We conducted an experimental evaluation comparing this adaptive agent with an agent that does not perceive nor use... Read more

Pedagogical agents – lifelike characters that guide users through multimedia learning environments – are intended to facilitate the learning process. According to social agency theory, the presentation of social cues (the image and voice of the agent) may prime the social interaction schema and cause the learner to deeply process the learning material. Research on pedagogical agents focuses mainly on either the role of the presence of pedagogical agents, by comparing agent and no-agent groups,... Read more

Numerous studies have tested the effects of pedagogical agents on learning and the influence of their specific appearance. What has not been analyzed, however, is whether an agent can have indirect effects when it is employed as a tutor for learning strategies rather than directly teaching the relevant learning material. In a between-subjects design (N = 45) we compared two different kinds of pedagogical agents – a cartoon-like rabbit and a realistic anthropomorphic agent –... Read more

Episodic memory is an important component of “minds” of many long-living virtual agents, for instance non-player characters from role-playing games. So far, research on episodic memory modeling in the context of these agents has focused mostly on producing the memory content online, that is, when the agent is being simulated. In this paper, we address a complementary issue: automatic generation of the memory content off-line. The intended use is generating memories that anticipate the start... Read more

The link between affect and student learning has been the subject of increasing attention. Because of the possible impacts of affective state on learning, it is a goal of many intelligent tutoring systems to attempt to control student emotional states through affective interventions. While much work has gone into improving the quality of these interventions, we are only beginning to understand the complexities of the relationships between affect, learning, and feedback. This paper investigates the... Read more

This paper presents the work to enhance virtual agents with the abilities of interacting with the environment and planning based on goals and internal states. We describe how we designed intelligent virtual agents that are able to perform tasks on a high-risk plant and that respond to expected as well as unexpected events. We proposed an informed virtual environment where agents are able to interact with other agents or avatars. By enhancing their reasoning abilities... Read more

This paper provides a method to make locomotion animation using riding motion, which is synthesized by computer simulation. Our locomotion system uses riding motion to avoid collision between objects instead of traditional obstacle avoidance. The two-dimensional locomotion using obstacle avoidance has a problem in that positions that the agent move is limited if the number of agents is large. In game or film, user or artist should throw up natural movement to locate agents in... Read more

Episodic memory (EM) is an umbrella term for memory systems that operate with representations of personal history of an entity. The content of EM is related to particular places and moments, and connected to subjective feelings and current goals. Recently, it has been argued that EM is one of the key components contributing to believability of intelligent virtual agents (IVAs), at least when agents interact with humans for more than a couple of minutes, because it... Read more