Modeling the user state for context-aware spoken interaction in ambient assisted living

Ambient Assisted Living (AAL) systems must provide adapted services easily accessible by a wide variety of users. This can only be possible if the communication between the user and the system is carried out through an interface that is simple, rapid, effective, and robust. Natural language interfaces such as dialog systems fulfill these requisites, as they are based on a spoken conversation that resembles human communication. In this paper, we enhance systems interacting in AAL domains by means of incorporating context-aware conversational agents that consider the external context of the interaction and predict the user's state. The user's state is built on the basis of their emotional state and intention, and it is recognized by means of a module conceived as an intermediate phase between natural language understanding and dialog management in the architecture of the conversational agent. This prediction, carried out for each user turn in the dialog, makes it possible to adapt the system dynamically to the user's needs. We have evaluated our proposal developing a context-aware system adapted to patients suffering from chronic pulmonary diseases, and provide a detailed discussion of the positive influence of our proposal in the success of the interaction, the information and services provided, as well as the perceived quality.This work was supported in part by Projects MINECO TEC2012-37832-C02-01, CICYT TEC2011-28626-C02- 02, CAM CONTEXTS (S2009/TIC-1485

A Satisfaction-based Model for Affect Recognition from Conversational Features in Spoken Dialog Systems

Detecting user affect automatically during real-time conversation is the main challenge towards our greater aim of infusing social intelligence into a natural-language mixed-initiative High-Fidelity (Hi-Fi) audio control spoken dialog agent. In recent years, studies on affect detection from voice have moved on to using realistic, non-acted data, which is subtler. However, it is more challenging to perceive subtler emotions and this is demonstrated in tasks such as labelling and machine prediction. This paper attempts to address part of this challenge by considering the role of user satisfaction ratings and also conversational/dialog features in discriminating contentment and frustration, two types of emotions that are known to be prevalent within spoken human-computer interaction. However, given the laboratory constraints, users might be positively biased when rating the system, indirectly making the reliability of the satisfaction data questionable. Machine learning experiments were conducted on two datasets, users and annotators, which were then compared in order to assess the reliability of these datasets. Our results indicated that standard classifiers were significantly more successful in discriminating the abovementioned emotions and their intensities (reflected by user satisfaction ratings) from annotator data than from user data. These results corroborated that: first, satisfaction data could be used directly as an alternative target variable to model affect, and that they could be predicted exclusively by dialog features. Second, these were only true when trying to predict the abovementioned emotions using annotator?s data, suggesting that user bias does exist in a laboratory-led evaluation

Processing and fusioning multiple heterogeneous information sources in multimodal dialog systems

Proceedings of: 17th International Conference on Information Fusion (FUSION 2014): Salamanca, Spain 7-10 July 2014.Context-aware dialog systems must be able to process very heterogeneous information sources and user input modes. In this paper we propose a method to fuse multimodal inputs into a unified representation. This representation allows the dialog manager of the system to find the best interaction strategy and also select the next system response. We show the applicability of our proposal by means of the implementation of a dialog system that considers spoken, tactile, and also information related to the context of the interaction with its users. Context information is related to the detection of user's intention during the dialog and their emotional state (internal context), and the user's location (external context).This work was supported in part by Projects MINECO TEC2012-37832-C02-01, CICYT TEC2011-28626-C02-02, CAM CONTEXTS (S2009/TIC-1485).Publicad

Developing enhanced conversational agents for social virtual worlds

In This Paper, We Present A Methodology For The Development Of Embodied Conversational Agents For Social Virtual Worlds. The Agents Provide Multimodal Communication With Their Users In Which Speech Interaction Is Included. Our Proposal Combines Different Techniques Related To Artificial Intelligence, Natural Language Processing, Affective Computing, And User Modeling. A Statistical Methodology Has Been Developed To Model The System Conversational Behavior, Which Is Learned From An Initial Corpus And Improved With The Knowledge Acquired From The Successive Interactions. In Addition, The Selection Of The Next System Response Is Adapted Considering Information Stored Into User&#39 S Profiles And Also The Emotional Contents Detected In The User&#39 S Utterances. Our Proposal Has Been Evaluated With The Successful Development Of An Embodied Conversational Agent Which Has Been Placed In The Second Life Social Virtual World. The Avatar Includes The Different Models And Interacts With The Users Who Inhabit The Virtual World In Order To Provide Academic Information. The Experimental Results Show That The Agent&#39 S Conversational Behavior Adapts Successfully To The Specific Characteristics Of Users Interacting In Such Environments.Work partially supported by the Spanish CICyT Projects under grant TRA2015-63708-R and TRA2016-78886-C3-1-R