The Role of Trust in Proactive Conversational Assistants Kraus, Matthias Callejas Carrión, Zoraida Human-computer-interaction Human-computer trust Proactivity Spoken dialogue system This work was supported in part by the German Federal Ministry of Education and Research through the Project ``RobotKoop: Cooperative Interaction Strategies and Goal Negotiations with Learning Autonomous Robots,'' and in part by the European Union's Horizon 2020 Research and Innovation Program through MENHIR: Mental health monitoring through interactive conversations (https://menhir-project.eu) under Agreement No 823907. Humans and machines harmoniously collaborating and benefiting from each other is a long lasting dream for researchers in robotics and artificial intelligence. An important feature of efficient and rewarding cooperation is the ability to assume possible problematic situations and act in advance to prevent negative outcomes. This concept of assistance is known under the term proactivity. In this article, we investigate the development and implementation of proactive dialogues for fostering a trustworthy human-computer relationship and providing adequate and timely assistance. Here, we make several contributions. A formalisation of proactive dialogue in conversational assistants is provided. The formalisation forms a framework for integrating proactive dialogue in conversational applications. Additionally, we present a study showing the relations between proactive dialogue actions and several aspects of the perceived trustworthiness of a system as well as effects on the user experience. The results of the experiments provide significant contributions to the line of proactive dialogue research. Particularly, we provide insights on the effects of proactive dialogue on the human-computer trust relationship and dependencies between proactive dialogue and user specific and situational characteristics. 2021-10-13T10:06:45Z 2021-10-13T10:06:45Z 2021-08-09 journal article M. Kraus... [et al.]. "The Role of Trust in Proactive Conversational Assistants," in IEEE Access, vol. 9, pp. 112821-112836, 2021, doi: [10.1109/ACCESS.2021.3103893] http://hdl.handle.net/10481/70822 10.1109/ACCESS.2021.3103893 eng info:eu-repo/grantAgreement/EC/H2020/823907 http://creativecommons.org/licenses/by/3.0/es/ open access Atribución 3.0 España IEEE