Tellols Asensi, DolçaLópez Sánchez, MaiteRodríguez Santiago, InmaculadaAlmajano, PabloPuig Puig, Anna2023-01-312023-01-312020-010167-8655https://hdl.handle.net/2445/192860Within the area of intelligent User Interfaces, we propose what we call Sentient Embodied Conversational Agents (SECAs): virtual characters able to engage users in complex conversations and to incorporate sentient capabilities similar to the ones humans have. This paper introduces SECAs together with their architecture and a publicly available software library that facilitates their inclusion in applications -such as educational and elder-care- requiring proactive and sensitive agent behaviours. In fact, we illustrate our proposal with a virtual tutor embedded in an educational application for children. The evaluation was performed in two stages: firstly, we tested a version with basic textual processing capabilities; and secondly, we evaluated a SECA with Machine-Learning enhanced user understanding capabilities. The results show a significant improvement in users' perception of the agent's understanding capability. Indeed, the Response Error Rate decreased from 22.31% to 11.46% when using ML techniques. Moreover, 99.33% of the participants consider the global experience of talking with the virtual tutor with sentient capabilities to be satisfactory.7 p.application/pdfengcc-by-nc-nd (c) Elsevier B.V., 2020https://creativecommons.org/licenses/by-nc-nd/4.0/Interpolació (Matemàtica)Teoria de l'aproximacióDisseny assistit per ordinadorSistemes informàtics interactiusAprenentatge automàticInterpolationApproximation theoryComputer-aided designInteractive computer systemsMachine learninginfo:eu-repo/semantics/article6995952023-01-31info:eu-repo/semantics/openAccess