Does Social Interaction Improve Learning Outcomes? Evidence from Field Experiments on Massive Open Online Courses

This paper studies how service providers can design social interaction among participants and quantify the causal impact of that interaction on service quality. We focus on education and analyze whether encouraging social interaction among students improves learning outcomes in massive open online courses (MOOCs), which are a new service delivery channel with universal access at reduced, if not zero, cost. We analyze three randomized experiments in a MOOC with more than 30,317 students from 183 countries. Two experiments study large-group interaction by encouraging a random subset of students to visit the course discussion board. The majority of students treated in these experiments had higher social engagement, higher quiz completion rates, and higher course grades. Using these treatments as instrumental variables, we estimate that one additional board visit causally increases the probability that a student finishes the quiz in the subsequent week by up to 4.3%. The third experiment studies small-group interaction by encouraging a random subset of students to conduct one-on-one synchronous discussions. Students who followed through and actually conducted pairwise discussions increased their quiz completion rates and quiz scores by 10% in the subsequent week. Combining results from these three experiments, we provide recommendations for designing social interaction mechanisms to improve service quality.