Scaffolding the human partner by contrastive guidance in an explanatory human-robot dialogue

André Groß; Amit Singh; Ngoc Chi Banh; Birte Richter; Ingrid Scharlau; Katharina J Rohlfing; Britta Wrede

doi:10.3389/frobt.2023.1236184

Scaffolding the human partner by contrastive guidance in an explanatory human-robot dialogue

Front Robot AI. 2023 Oct 30:10:1236184. doi: 10.3389/frobt.2023.1236184. eCollection 2023.

Authors

André Groß^{1

2}, Amit Singh³, Ngoc Chi Banh⁴, Birte Richter^{1

2}, Ingrid Scharlau⁴, Katharina J Rohlfing³, Britta Wrede^{1

2}

Affiliations

¹ Medical Assistance Systems, Medical School OWL, Bielefeld University, Bielefeld, Germany.
² Center for Cognitive Interaction Technology, CITEC, Bielefeld University, Bielefeld, Germany.
³ Psycholinguistics, Faculty of Arts and Humanities, Paderborn University, Paderborn, Germany.
⁴ Cognitive Psychology, Faculty of Arts and Humanities, Paderborn University, Paderborn, Germany.

Abstract

Explanation has been identified as an important capability for AI-based systems, but research on systematic strategies for achieving understanding in interaction with such systems is still sparse. Negation is a linguistic strategy that is often used in explanations. It creates a contrast space between the affirmed and the negated item that enriches explaining processes with additional contextual information. While negation in human speech has been shown to lead to higher processing costs and worse task performance in terms of recall or action execution when used in isolation, it can decrease processing costs when used in context. So far, it has not been considered as a guiding strategy for explanations in human-robot interaction. We conducted an empirical study to investigate the use of negation as a guiding strategy in explanatory human-robot dialogue, in which a virtual robot explains tasks and possible actions to a human explainee to solve them in terms of gestures on a touchscreen. Our results show that negation vs. affirmation 1) increases processing costs measured as reaction time and 2) increases several aspects of task performance. While there was no significant effect of negation on the number of initially correctly executed gestures, we found a significantly lower number of attempts-measured as breaks in the finger movement data before the correct gesture was carried out-when being instructed through a negation. We further found that the gestures significantly resembled the presented prototype gesture more following an instruction with a negation as opposed to an affirmation. Also, the participants rated the benefit of contrastive vs. affirmative explanations significantly higher. Repeating the instructions decreased the effects of negation, yielding similar processing costs and task performance measures for negation and affirmation after several iterations. We discuss our results with respect to possible effects of negation on linguistic processing of explanations and limitations of our study.

Keywords: HRI; XAI; explaining; gesture; negation; touch interaction; understanding.

Grants and funding

Funded by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation): TRR 318/1 2021-438445824 “Constructing Explainability” and we acknowledge the financial support of the Open Access Publication Fund of Bielefeld University for the article processing charge.