Introduction: Our Love Affair with Psychology

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The field of Human-Robot Interaction, and in particular, the field of social HRI is nurtured by the weaving of different scientific perspectives. As a community, we recognise that the technical fields of engineering, control theory or computer science do not provide much tooling for the scientific investigation of the ‘Human’ and ’Interaction’ parts of HRI. For this reason, we take inspiration and ground much of our research in established results from social sciences – in our field, primarily social psychology, developmental psychology, and sociology. As academics, we pride ourselves on standing at the intersection of these many fields, being able to understand and be understood by programmers, engineers, as well as psychologists. In this sense, our field embodies the basic idea of cognitive sciences: building bridges across disciplines to gain new insights on complex scientific challenges.
That said, the demographics of the academics working in HRI are skewed towards engineering background TBD: any data to support that? We could try to go over last year HRI’s author list, and quickly check the backgrounds?: one often becomes a researcher in HRI by first building robots and then looking at how the machines might interact with humans. While some of us do have a primarily academic background in psychology, many do not. This is not per se an issue: as capable, rigorous scientists, we can read and understand the literature of social science, and take inspirations or reproduce tasks, protocols, results. This is actually how science is supposed to work.
We think however that a ‘second order’ effect might be underestimated: because many of us are ‘consumers’ of the psychology literature rather than ‘producers’ and active contributor to the psychology community, we might not always share the same common-grounds with these neighbouring academic fields.
This has two consequences: first, as we are generally less familiar with different social science academic communities, we tend to be less critical and we would not automatically question their findings as we would in our own community. This effect is reinforced by the perceived maturity of academic fields like social or developmental psychology, versus the youth of human-robot interaction.
Second, we build assumptions on how research is conducted in other communities based on our own experience. As our background is often in exact sciences, we would intuitively expect evaluation methods to deliver as much as possible robust, exact, clear-cut results. Results that are always reproducible. And we are certainly embarrassed whenever our results do not draw such a clear, legible picture.
It is reasonable to think that, consciously or not, we assume the same ‘exact science’ mindset across all scientific discipline, including social sciences. Accordingly, we do not tend to question their established results.
However, over the last years, a growing evidence has built up that show that many of these ‘classical’, ‘established’ results from social sciences – psychology in particular – might not be as solid and clear as assumed: to much ado, a recently published article \cite{rpp} evidenced the difficulty to reproduce several key results from psychology: out of 100 studies sampled from a range of psychology sub-fields, only 36% of the replication studies found significant results whereas 97% of the original studies reported significant effects. The results of two third of 100 studies could not be properly replicated: whatever the reasons might be (from publication bias, to sociological changes in the population, to small effect sizes), it calls for exerting caution whenever we build upon supposedly established results.
Mention that findings true 50 years ago might not be true anymore today?
We are convinced that many researchers in HRI are already aware of these issues. The purpose of the article is to make this concern (“we rely too much and too blindly on results from psychology that might not hold”) surface within the HRI community. To illustrate the point, we present hereafter two unsuccessful attempts at reproducing the effect of social facilitation in presence of robots: social facilitation is an effect where the mere presence of a (silent, passive) external agent influences one’s behaviour: the participant would perform better or worst, depending on the task and on the expectations. A large body of psychology literature evidence this effect, that has been studied in robotics as well. However careful our experimental design was, we have not been able to reproduce the effect.