  A significant number of college students suffer from mental health issues
that impact their physical, social, and occupational outcomes. Various scalable
technologies have been proposed in order to mitigate the negative impact of
mental health disorders. However, the evaluation for these technologies, if
done at all, often reports mixed results on improving users' mental health. We
need to better understand the factors that align a user's attributes and needs
with technology-based interventions for positive outcomes. In psychotherapy
theory, therapeutic alliance and rapport between a therapist and a client is
regarded as the basis for therapeutic success. In prior works, social robots
have shown the potential to build rapport and a working alliance with users in
various settings. In this work, we explore the use of a social robot coach to
deliver positive psychology interventions to college students living in
on-campus dormitories. We recruited 35 college students to participate in our
study and deployed a social robot coach in their room. The robot delivered
daily positive psychology sessions among other useful skills like delivering
the weather forecast, scheduling reminders, etc. We found a statistically
significant improvement in participants' psychological wellbeing, mood, and
readiness to change behavior for improved wellbeing after they completed the
study. Furthermore, students' personality traits were found to have a
significant association with intervention efficacy. Analysis of the post-study
interview revealed students' appreciation of the robot's companionship and
their concerns for privacy.
