We present pilot data for one of the first comprehensive investigations of Intergroup Contact Theory [1], [2] in the context of human-robot interaction. Applying an actual intergroup contact procedure known to affect intergroup attitudes among humans (e.g., [3]), we examined whether human-robot interaction as a positive intergroup contact would change participants' evaluation of robots. Our data from 28 student participants ($N=15$in the interaction condition and$N=13$in the no-interaction condition) suggest that after the participant and robot self-disclosed to each other (Fast Friendship Task), participants (1) felt more positive emotions towards robots, (2) perceived robots as warmer, and (3) identified robots as more similar to humans. These preliminary findings invite further research on the application of Intergroup Contact Theory in examining social human-robot interaction and its possible contributions to understanding human psychology.

This video illustrates the large-scale experiment of the L2TOR project that will be presented at the HRI 2019 conference. The experiment aimed to investigate how 192 Dutch 5-year-old children could learn 34 English words from a NAO robot in 7 lessons. The experiment compared 4 conditions: 1) robot using iconic gestures, 2) robot without iconic gestures, 3) tablet only, and 4) a control group. The results revealed that children could learn more English words in all experimental conditions compared to the control group. The three experimental conditions did not show any significant differences regarding the learning outcomes.

We present a large-scale study of a series of seven lessons designed to help young children learn English vocabulary as a foreign language using a social robot. The experiment was designed to investigate 1) the effectiveness of a social robot teaching children new words over the course of multiple interactions (supported by a tablet), 2) the added benefit of a robot's iconic gestures on word learning and retention, and 3) the effect of learning from a robot tutor accompanied by a tablet versus learning from a tablet application alone. For reasons of transparency, the research questions, hypotheses and methods were preregistered. With a sample size of 194 children, our study was statistically well-powered. Our findings demonstrate that children are able to acquire and retain English vocabulary words taught by a robot tutor to a similar extent as when they are taught by a tablet application. In addition, we found no beneficial effect of a robot's iconic gestures on learning gains.

We conducted a study with 25 children to investigate the effectiveness of a robot measuring and encouraging production of spatial concepts in a second language compared to a human experimenter. Productive vocabulary is often not measured in second language learning, due to the difficulty of both learning and assessing productive learning gains. We hypothesized that a robot peer may help assessing productive vocabulary. Previous studies on foreign language learning have found that robots can help to reduce language anxiety, leading to improved results. In our study we found that a robot is able to reach a similar performance to the experimenter in getting children to produce, despite the person's advantages in social ability, and discuss the extent to which a robot may be suitable for this task.