Cognitive aspects of embodied conversational agents

Page 2 of 215 Abstract Embodied Conversational Agents (ECA) seek to provide a more natural means of interaction for a user through conversation. ECA build on the dialogue abilities of spoken dialogue systems with the provision of a physical or virtual avatar. The rationale for this Thesis is that an ECA should be able to support a form of conversation capable of understanding both the content and affect of the dialogue and providing a meaningful response. The aim is to examine the cognitive aspects of ECA attempting such conversational dialogue in order to augment the abilities of dialogue management. The focus is on the provision of cognitive functions, outside of dialogue control, for managing the relationship with the user including the user’s emotional state. This will include a definition of conversation and an examination of the cognitive mechanisms that underpin meaningful conversation. The scope of this Thesis considers the development of a Companion ECA, the ‘How Was Your Day’ (HWYD) Companion, which enters into an open conversation with the user about the events of their day at work. The HWYD Companion attempts to positively influence the user’s attitude to these events. The main focus of this Thesis is on the Affective Strategy Module (ASM) which will attend to the information covering these events and the user’s emotional state in order to generate a plan for a narrative response. Within this narrative response the ASM will embed a means of influence acting upon the user’s attitude to the events. The HYWD Companion has contributed to the work on ECA through the provision of a system engaging in conversational dialogue including the affective aspects of such dialogue. This supports open conversation with longer utterances than typical taskoriented dialogue systems and can handle user interruptions. The main work of this Thesis provides a major component of this overall contribution and, in addition, provides a specific contribution of its own with the provision of narrative persuasion.